diff --git a/.gitignore b/.gitignore
index 4c8e2f6d8..95b2812b7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,7 @@ test/auth.dat
 .coverage
 dist
 cover
+*.pem
+*.cer
+inf.dat
+radl
diff --git a/IM/CloudInfo.py b/IM/CloudInfo.py
index 1338583b1..f1fe068ab 100644
--- a/IM/CloudInfo.py
+++ b/IM/CloudInfo.py
@@ -46,7 +46,7 @@ def getCloudConnector(self):
         try:
             module = __import__('IM.connectors.' + self.type, fromlist=[self.type + "CloudConnector"])
             return getattr(module, self.type + "CloudConnector")(self)
-        except Exception, ex:
+        except Exception as ex:
             raise Exception("Cloud provider not supported: %s (error: %s)" % (self.type, str(ex)))
 
     def __str__(self):
diff --git a/IM/ConfManager.py b/IM/ConfManager.py
index de90064ec..2d97c67ef 100644
--- a/IM/ConfManager.py
+++ b/IM/ConfManager.py
@@ -23,14 +23,18 @@
 import shutil
 import json
 import copy
-from StringIO import StringIO
+
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 from multiprocessing import Queue
 
 from ansible.parsing.vault import VaultEditor
 
 from IM.ansible_utils.ansible_launcher import AnsibleThread
 
-import InfrastructureManager
+import IM.InfrastructureManager
 from IM.VirtualMachine import VirtualMachine
 from IM.SSH import AuthenticationException
 from IM.SSHRetry import SSHRetry
@@ -68,7 +72,7 @@ def check_running_pids(self, vms_configuring):
         Update the status of the configuration processes
         """
         res = {}
-        for step, vm_list in vms_configuring.iteritems():
+        for step, vm_list in vms_configuring.items():
             for vm in vm_list:
                 if isinstance(vm, VirtualMachine):
                     # Update the info of the VM to check it is in a correct
@@ -113,7 +117,7 @@ def check_running_pids(self, vms_configuring):
     def stop(self):
         self._stop = True
         # put a task to assure to wake up the thread
-        self.inf.ctxt_tasks.put((-10, 0, None, None))
+        self.inf.add_ctxt_tasks([(-10, 0, None, None)])
         ConfManager.logger.debug(
             "Inf ID: " + str(self.inf.id) + ": Stop Configuration thread.")
         if self.ansible_process and self.ansible_process.is_alive():
@@ -803,7 +807,7 @@ def configure_master(self):
 
                     success = configured_ok
 
-                except Exception, ex:
+                except Exception as ex:
                     ConfManager.logger.exception(
                         "Inf ID: " + str(self.inf.id) + ": Error in the ansible installation process")
                     self.inf.add_cont_msg(
@@ -990,7 +994,7 @@ def generate_playbooks_and_hosts(self):
                 ssh.sftp_put_files(recipe_files)
 
             self.inf.set_configured(True)
-        except Exception, ex:
+        except Exception as ex:
             self.inf.set_configured(False)
             ConfManager.logger.exception(
                 "Inf ID: " + str(self.inf.id) + ": Error generating playbooks.")
@@ -1004,7 +1008,7 @@ def relaunch_vm(self, vm, failed_cloud=False):
         Remove and launch again the specified VM
         """
         try:
-            removed = InfrastructureManager.InfrastructureManager.RemoveResource(
+            removed = IM.InfrastructureManager.InfrastructureManager.RemoveResource(
                 self.inf.id, vm.im_id, self.auth)
         except:
             ConfManager.logger.exception(
@@ -1025,7 +1029,7 @@ def relaunch_vm(self, vm, failed_cloud=False):
         failed_clouds = []
         if failed_cloud:
             failed_clouds = [vm.cloud]
-        InfrastructureManager.InfrastructureManager.AddResource(
+        IM.InfrastructureManager.InfrastructureManager.AddResource(
             self.inf.id, new_radl, self.auth, False, failed_clouds)
 
     def wait_vm_running(self, vm, timeout, relaunch=False):
@@ -1161,6 +1165,17 @@ def wait_vm_ssh_acccess(self, vm, timeout):
         # Timeout, return False
         return False, "Timeout waiting SSH access."
 
+    @staticmethod
+    def cmp_credentials(creds, other_creds):
+        if len(creds) != len(other_creds):
+            return 1
+        
+        for i in range(len(creds)):
+            if creds[i] != other_creds[i]:
+                return 1
+        
+        return 0
+
     def change_master_credentials(self, ssh):
         """
         Chech the RADL of the VM master to see if we must change the user credentials
@@ -1175,7 +1190,7 @@ def change_master_credentials(self, ssh):
             new_creds = self.inf.vm_master.getCredentialValues(new=True)
             if len(list(set(new_creds))) > 1 or list(set(new_creds))[0] is not None:
                 change_creds = False
-                if cmp(new_creds, creds) != 0:
+                if self.cmp_credentials(new_creds, creds) != 0:
                     (_, new_passwd, new_public_key, new_private_key) = new_creds
                     # only change to the new password if there are a previous
                     # passwd value
@@ -1234,7 +1249,7 @@ def call_ansible(self, tmp_dir, inventory, playbook, ssh):
                 pk_out = open(gen_pk_file, 'w')
                 pk_out.write(ssh.private_key)
                 pk_out.close()
-                os.chmod(gen_pk_file, 0400)
+                os.chmod(gen_pk_file, 0o400)
         else:
             gen_pk_file = None
 
@@ -1414,7 +1429,7 @@ def configure_ansible(self, ssh, tmp_dir):
                 ConfManager.logger.debug("Inf ID: " + str(self.inf.id) +
                                          ": Ansible successfully configured in the master VM:\n" + msg + "\n\n")
                 self.inf.add_cont_msg("Ansible successfully configured in the master VM.")
-        except Exception, ex:
+        except Exception as ex:
             ConfManager.logger.exception(
                 "Inf ID: " + str(self.inf.id) + ": Error configuring master node.")
             self.inf.add_cont_msg("Error configuring master node: " + str(ex))
@@ -1456,7 +1471,7 @@ def create_general_conf_file(self, conf_file, vm_list):
                  _, vm_conf_data['private_key']) = creds
                 # If there are new creds to set to the VM
                 if len(list(set(new_creds))) > 1 or list(set(new_creds))[0] is not None:
-                    if cmp(new_creds, creds) != 0:
+                    if self.cmp_credentials(new_creds, creds) != 0:
                         (_, vm_conf_data['new_passwd'], vm_conf_data[
                          'new_public_key'], vm_conf_data['new_private_key']) = new_creds
 
diff --git a/IM/InfrastructureInfo.py b/IM/InfrastructureInfo.py
index e7710bcd6..0181efe4a 100644
--- a/IM/InfrastructureInfo.py
+++ b/IM/InfrastructureInfo.py
@@ -20,13 +20,16 @@
 from uuid import uuid1
 import json
 
-from ganglia import ganglia_info
-import ConfManager
+from IM.ganglia import ganglia_info
+import IM.ConfManager
 from datetime import datetime
 from radl.radl import RADL, Feature, deploy, system, contextualize_item
 from radl.radl_json import parse_radl as parse_radl_json, dump_radl as dump_radl_json
-from config import Config
-from Queue import PriorityQueue
+from IM.config import Config
+try:
+    from Queue import PriorityQueue
+except ImportError:
+    from queue import PriorityQueue
 from IM.VirtualMachine import VirtualMachine
 from IM.auth import Authentication
 
@@ -180,7 +183,11 @@ def add_cont_msg(self, msg):
         """
         Add a line to the contextualization message
         """
-        self.cont_out += str(datetime.now()) + ": " + str(msg.decode('utf8', 'ignore')) + "\n"
+        try:
+            str_msg = str(msg.decode('utf8', 'ignore'))
+        except:
+            str_msg = msg
+        self.cont_out += str(datetime.now()) + ": " + str_msg + "\n"
 
     def get_vm_list(self):
         """
@@ -359,7 +366,7 @@ def update_ganglia_info(self):
             if now - self.last_ganglia_update > Config.GANGLIA_INFO_UPDATE_FREQUENCY:
                 try:
                     (success, msg) = ganglia_info.update_ganglia_info(self)
-                except Exception, ex:
+                except Exception as ex:
                     success = False
                     msg = str(ex)
             else:
@@ -505,7 +512,7 @@ def Contextualize(self, auth, vm_list=None):
             self.add_ctxt_tasks(ctxt_task)
 
             if self.cm is None or not self.cm.isAlive():
-                self.cm = ConfManager.ConfManager(self, auth, max_ctxt_time)
+                self.cm = IM.ConfManager.ConfManager(self, auth, max_ctxt_time)
                 self.cm.start()
             else:
                 # update the ConfManager reference to the inf object
diff --git a/IM/InfrastructureList.py b/IM/InfrastructureList.py
index 12b68a7c7..62ec85c41 100644
--- a/IM/InfrastructureList.py
+++ b/IM/InfrastructureList.py
@@ -92,7 +92,7 @@ def load_data():
             try:
                 inf_list = InfrastructureList._get_data_from_db(Config.DATA_DB)
                 InfrastructureList.infrastructure_list = inf_list
-            except Exception, ex:
+            except Exception as ex:
                 InfrastructureList.logger.exception("ERROR loading data. Correct or delete it!!")
                 sys.stderr.write("ERROR loading data: " + str(ex) + ".\nCorrect or delete it!! ")
                 sys.exit(-1)
@@ -114,7 +114,7 @@ def save_data(inf_id=None):
                 if not res:
                     InfrastructureList.logger.error("ERROR saving data.\nChanges not stored!!")
                     sys.stderr.write("ERROR saving data.\nChanges not stored!!")
-            except Exception, ex:
+            except Exception as ex:
                 InfrastructureList.logger.exception("ERROR saving data. Changes not stored!!")
                 sys.stderr.write("ERROR saving data: " + str(ex) + ".\nChanges not stored!!")
 
diff --git a/IM/InfrastructureManager.py b/IM/InfrastructureManager.py
index 32e93f14d..a9a6b63ab 100755
--- a/IM/InfrastructureManager.py
+++ b/IM/InfrastructureManager.py
@@ -478,8 +478,7 @@ def AddResource(inf_id, radl_data, auth, context=True, failed_clouds=[]):
         # NOTE: consider fake deploys (vm_number == 0)
         deploys_group_cloud_list = {}
         for deploy_group in deploy_groups:
-            suggested_cloud_ids = list(
-                set([d.cloud_id for d in deploy_group if d.cloud_id]))
+            suggested_cloud_ids = list(set([d.cloud_id for d in deploy_group if d.cloud_id]))
             if len(suggested_cloud_ids) > 1:
                 raise Exception("Two deployments that have to be launched in the same cloud provider "
                                 "are asked to be deployed in different cloud providers: %s" % deploy_group)
@@ -493,11 +492,16 @@ def AddResource(inf_id, radl_data, auth, context=True, failed_clouds=[]):
                         (suggested_cloud_ids[0], cloud_list[suggested_cloud_ids[0]])]
             else:
                 cloud_list0 = cloud_list.items()
-            if d.vm_number:
-                scored_clouds = [(cloud_id, sum([d.vm_number * concrete_systems[cloud_id][d.id][1]
-                                                 for d in deploy_group])) for cloud_id, _ in cloud_list0]
-            else:
-                scored_clouds = [(cloud_id, 1) for cloud_id, _ in cloud_list0]
+
+            scored_clouds = []
+            for cloud_id, _ in cloud_list0:
+                total = 0
+                for d in deploy_group:
+                    if d.vm_number:
+                        total += d.vm_number * concrete_systems[cloud_id][d.id][1]
+                    else:
+                        total += 1
+                scored_clouds.append((cloud_id, total))
 
             ordered_cloud_list = [c.id for c in CloudInfo.get_cloud_list(auth)]
             # reverse the list to use the reverse order in the sort function
@@ -559,7 +563,7 @@ def AddResource(inf_id, radl_data, auth, context=True, failed_clouds=[]):
             if passwd and not new_passwd:
                 # The VM uses the VMI password, set to change it
                 random_password = ''.join(random.choice(
-                    string.letters + string.digits) for _ in range(8))
+                    string.ascii_letters + string.digits) for _ in range(8))
                 vm.info.systems[0].setCredentialValues(
                     password=random_password, new=True)
 
diff --git a/IM/REST.py b/IM/REST.py
index f27703280..3d9a4f047 100644
--- a/IM/REST.py
+++ b/IM/REST.py
@@ -241,13 +241,13 @@ def RESTDestroyInfrastructure(id=None):
         InfrastructureManager.DestroyInfrastructure(id, auth)
         bottle.response.content_type = "text/plain"
         return ""
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Destroying Inf: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Destroying Inf: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Destroying Inf: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Destroying Inf")
         return return_error(400, "Error Destroying Inf: " + str(ex))
 
@@ -271,13 +271,13 @@ def RESTGetInfrastructureInfo(id=None):
                        'HTTP_HOST'] + '/infrastructures/' + str(id) + '/vms/' + str(vm_id))
 
         return format_output(res, "text/uri-list", "uri-list", "uri")
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Getting Inf. info: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Getting Inf. info: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Getting Inf. info: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Getting Inf. info")
         return return_error(400, "Error Getting Inf. info: " + str(ex))
 
@@ -305,13 +305,13 @@ def RESTGetInfrastructureProperty(id=None, prop=None):
             return return_error(404, "Incorrect infrastructure property")
 
         return format_output(res, field_name=prop)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Getting Inf. prop: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Getting Inf. prop: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Getting Inf. prop: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Getting Inf. prop")
         return return_error(400, "Error Getting Inf. prop: " + str(ex))
 
@@ -335,9 +335,9 @@ def RESTGetInfrastructureList():
                 protocol + bottle.request.environ['HTTP_HOST'] + "/infrastructures/" + str(inf_id))
 
         return format_output(res, "text/uri-list", "uri-list", "uri")
-    except InvaliddUserException, ex:
+    except InvaliddUserException as ex:
         return return_error(401, "Error Getting Inf. List: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Getting Inf. List")
         return return_error(400, "Error Getting Inf. List: " + str(ex))
 
@@ -374,9 +374,9 @@ def RESTCreateInfrastructure():
             "/infrastructures/" + str(inf_id)
 
         return format_output(res, "text/uri-list", "uri")
-    except InvaliddUserException, ex:
+    except InvaliddUserException as ex:
         return return_error(401, "Error Getting Inf. info: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Creating Inf.")
         return return_error(400, "Error Creating Inf.: " + str(ex))
 
@@ -391,17 +391,17 @@ def RESTGetVMInfo(infid=None, vmid=None):
     try:
         radl = InfrastructureManager.GetVMInfo(infid, vmid, auth)
         return format_output(radl, field_name="radl")
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Getting VM. info: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Getting VM. info: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Getting VM. info: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error Getting VM. info: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error Getting VM. info: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Getting VM info")
         return return_error(400, "Error Getting VM info: " + str(ex))
 
@@ -423,17 +423,17 @@ def RESTGetVMProperty(infid=None, vmid=None, prop=None):
             return return_error(404, "Incorrect property %s for VM ID %s" % (prop, vmid))
         else:
             return format_output(info, field_name=prop)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Getting VM. property: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Getting VM. property: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Getting VM. property: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error Getting VM. property: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error Getting VM. property: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Getting VM property")
         return return_error(400, "Error Getting VM property: " + str(ex))
 
@@ -479,13 +479,13 @@ def RESTAddResource(id=None):
                        'HTTP_HOST'] + "/infrastructures/" + str(id) + "/vms/" + str(vm_id))
 
         return format_output(res, "text/uri-list", "uri-list", "uri")
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Adding resources: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Adding resources: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Adding resources: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Adding resources")
         return return_error(400, "Error Adding resources: " + str(ex))
 
@@ -511,17 +511,17 @@ def RESTRemoveResource(infid=None, vmid=None):
         InfrastructureManager.RemoveResource(infid, vmid, auth, context)
         bottle.response.content_type = "text/plain"
         return ""
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error Removing resources: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error Removing resources: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error Removing resources: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error Removing resources: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error Removing resources: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error Removing resources")
         return return_error(400, "Error Removing resources: " + str(ex))
 
@@ -548,17 +548,17 @@ def RESTAlterVM(infid=None, vmid=None):
         vm_info = InfrastructureManager.AlterVM(infid, vmid, radl_data, auth)
 
         return format_output(vm_info, field_name="radl")
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error modifying resources: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error modifying resources: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error modifying resources: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error modifying resources: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error modifying resources: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error modifying resources")
         return return_error(400, "Error modifying resources: " + str(ex))
 
@@ -594,13 +594,13 @@ def RESTReconfigureInfrastructure(id=None):
             radl_data = ""
         bottle.response.content_type = "text/plain"
         return InfrastructureManager.Reconfigure(id, radl_data, auth, vm_list)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error reconfiguring infrastructure: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error reconfiguring infrastructure: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error reconfiguring infrastructure: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error reconfiguring infrastructure")
         return return_error(400, "Error reconfiguring infrastructure: " + str(ex))
 
@@ -615,13 +615,13 @@ def RESTStartInfrastructure(id=None):
     try:
         bottle.response.content_type = "text/plain"
         return InfrastructureManager.StartInfrastructure(id, auth)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error starting infrastructure: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error starting infrastructure: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error starting infrastructure: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error starting infrastructure")
         return return_error(400, "Error starting infrastructure: " + str(ex))
 
@@ -636,13 +636,13 @@ def RESTStopInfrastructure(id=None):
     try:
         bottle.response.content_type = "text/plain"
         return InfrastructureManager.StopInfrastructure(id, auth)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error stopping infrastructure: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error stopping infrastructure: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error stopping infrastructure: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error stopping infrastructure")
         return return_error(400, "Error stopping infrastructure: " + str(ex))
 
@@ -657,17 +657,17 @@ def RESTStartVM(infid=None, vmid=None, prop=None):
     try:
         bottle.response.content_type = "text/plain"
         return InfrastructureManager.StartVM(infid, vmid, auth)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error starting VM: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error starting VM: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error starting VM: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error starting VM: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error starting VM: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error starting VM")
         return return_error(400, "Error starting VM: " + str(ex))
 
@@ -682,17 +682,17 @@ def RESTStopVM(infid=None, vmid=None, prop=None):
     try:
         bottle.response.content_type = "text/plain"
         return InfrastructureManager.StopVM(infid, vmid, auth)
-    except DeletedInfrastructureException, ex:
+    except DeletedInfrastructureException as ex:
         return return_error(404, "Error stopping VM: " + str(ex))
-    except IncorrectInfrastructureException, ex:
+    except IncorrectInfrastructureException as ex:
         return return_error(404, "Error stopping VM: " + str(ex))
-    except UnauthorizedUserException, ex:
+    except UnauthorizedUserException as ex:
         return return_error(403, "Error stopping VM: " + str(ex))
-    except DeletedVMException, ex:
+    except DeletedVMException as ex:
         return return_error(404, "Error stopping VM: " + str(ex))
-    except IncorrectVMException, ex:
+    except IncorrectVMException as ex:
         return return_error(404, "Error stopping VM: " + str(ex))
-    except Exception, ex:
+    except Exception as ex:
         logger.exception("Error stopping VM")
         return return_error(400, "Error stopping VM: " + str(ex))
 
@@ -702,7 +702,7 @@ def RESTGeVersion():
     try:
         from IM import __version__ as version
         return format_output(version, field_name="version")
-    except Exception, ex:
+    except Exception as ex:
         return return_error(400, "Error getting IM version: " + str(ex))
 
 
diff --git a/IM/SSH.py b/IM/SSH.py
index a2590bdd4..cb2621794 100755
--- a/IM/SSH.py
+++ b/IM/SSH.py
@@ -19,7 +19,10 @@
 import paramiko
 import scp
 import os
-import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 from threading import Thread
 
 
@@ -85,7 +88,7 @@ def __init__(self, host, user, passwd, private_key=None, port=22):
         self.private_key = private_key
         self.private_key_obj = None
         if (private_key is not None and private_key.strip() != ""):
-            private_key_obj = StringIO.StringIO()
+            private_key_obj = StringIO()
             if os.path.isfile(private_key):
                 pkfile = open(private_key)
                 for line in pkfile.readlines():
@@ -152,7 +155,7 @@ def test_connectivity(self, time_out=None):
             return True
         except paramiko.AuthenticationException:
             raise AuthenticationException("Authentication Error!!")
-        except paramiko.SSHException, e:
+        except paramiko.SSHException as e:
             if str(e) == "No authentication methods available":
                 raise AuthenticationException("Authentication Error!!")
             return False
@@ -314,9 +317,7 @@ def sftp_put_dir(self, src, dest):
                         except:
                             sftp.mkdir(dest_path)
                     else:
-                        out, err, code = self.execute(
-                            "mkdir -p %s" % dest_path)
-                        print out, err
+                        out, err, code = self.execute("mkdir -p %s" % dest_path)
                 for filename in filenames:
                     src_file = os.path.join(dirname, filename)
                     dest_file = os.path.join(dest, dirname[len(src) + 1:],
diff --git a/IM/ServiceRequests.py b/IM/ServiceRequests.py
index b7fd68c39..095145ecd 100644
--- a/IM/ServiceRequests.py
+++ b/IM/ServiceRequests.py
@@ -18,10 +18,10 @@
 
 import logging
 
-from request import Request, AsyncRequest
-import InfrastructureManager
+from IM.request import Request, AsyncRequest
+import IM.InfrastructureManager
 import IM.InfrastructureList
-from auth import Authentication
+from IM.auth import Authentication
 from IM import __version__ as version
 
 logger = logging.getLogger('InfrastructureManager')
@@ -119,7 +119,7 @@ def _execute(self):
             res = self._call_function()
             self.set(res)
             return True
-        except Exception, ex:
+        except Exception as ex:
             logger.exception(self._error_mesage)
             self.set(str(ex))
             return False
@@ -133,7 +133,7 @@ class Request_AddResource(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Adding resources."
         (inf_id, radl_data, auth_data, context) = self.arguments
-        return InfrastructureManager.InfrastructureManager.AddResource(inf_id, radl_data,
+        return IM.InfrastructureManager.InfrastructureManager.AddResource(inf_id, radl_data,
                                                                        Authentication(auth_data),
                                                                        context)
 
@@ -146,7 +146,7 @@ class Request_RemoveResource(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Removing resources."
         (inf_id, vm_list, auth_data, context) = self.arguments
-        return InfrastructureManager.InfrastructureManager.RemoveResource(inf_id, vm_list,
+        return IM.InfrastructureManager.InfrastructureManager.RemoveResource(inf_id, vm_list,
                                                                           Authentication(auth_data),
                                                                           context)
 
@@ -159,7 +159,7 @@ class Request_GetInfrastructureInfo(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Getting Inf. Info."
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetInfrastructureInfo(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetInfrastructureInfo(inf_id, Authentication(auth_data))
 
 
 class Request_GetVMInfo(IMBaseRequest):
@@ -170,7 +170,7 @@ class Request_GetVMInfo(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Getting VM Info."
         (inf_id, vm_id, auth_data) = self.arguments
-        return str(InfrastructureManager.InfrastructureManager.GetVMInfo(inf_id, vm_id, Authentication(auth_data)))
+        return str(IM.InfrastructureManager.InfrastructureManager.GetVMInfo(inf_id, vm_id, Authentication(auth_data)))
 
 
 class Request_GetVMProperty(IMBaseRequest):
@@ -181,7 +181,7 @@ class Request_GetVMProperty(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Getting VM Property."
         (inf_id, vm_id, property_name, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetVMProperty(inf_id, vm_id, property_name,
+        return IM.InfrastructureManager.InfrastructureManager.GetVMProperty(inf_id, vm_id, property_name,
                                                                          Authentication(auth_data))
 
 
@@ -193,7 +193,7 @@ class Request_AlterVM(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Changing VM Info."
         (inf_id, vm_id, radl, auth_data) = self.arguments
-        return str(InfrastructureManager.InfrastructureManager.AlterVM(inf_id, vm_id, radl, Authentication(auth_data)))
+        return str(IM.InfrastructureManager.InfrastructureManager.AlterVM(inf_id, vm_id, radl, Authentication(auth_data)))
 
 
 class Request_DestroyInfrastructure(IMBaseRequest):
@@ -204,7 +204,7 @@ class Request_DestroyInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Destroying Inf."
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.DestroyInfrastructure(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.DestroyInfrastructure(inf_id, Authentication(auth_data))
 
 
 class Request_StopInfrastructure(IMBaseRequest):
@@ -215,7 +215,7 @@ class Request_StopInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Stopping Inf."
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.StopInfrastructure(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.StopInfrastructure(inf_id, Authentication(auth_data))
 
 
 class Request_StartInfrastructure(IMBaseRequest):
@@ -226,7 +226,7 @@ class Request_StartInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Starting Inf."
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.StartInfrastructure(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.StartInfrastructure(inf_id, Authentication(auth_data))
 
 
 class Request_CreateInfrastructure(IMBaseRequest):
@@ -237,7 +237,7 @@ class Request_CreateInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Creating Inf."
         (radl_data, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.CreateInfrastructure(radl_data, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.CreateInfrastructure(radl_data, Authentication(auth_data))
 
 
 class Request_GetInfrastructureList(IMBaseRequest):
@@ -248,7 +248,7 @@ class Request_GetInfrastructureList(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Getting Inf. List."
         (auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetInfrastructureList(Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetInfrastructureList(Authentication(auth_data))
 
 
 class Request_Reconfigure(IMBaseRequest):
@@ -259,7 +259,7 @@ class Request_Reconfigure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Reconfiguring Inf."
         (inf_id, radl_data, auth_data, vm_list) = self.arguments
-        return InfrastructureManager.InfrastructureManager.Reconfigure(inf_id, radl_data,
+        return IM.InfrastructureManager.InfrastructureManager.Reconfigure(inf_id, radl_data,
                                                                        Authentication(auth_data), vm_list)
 
 
@@ -271,7 +271,7 @@ class Request_ImportInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Importing Inf."
         (str_inf, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.ImportInfrastructure(str_inf, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.ImportInfrastructure(str_inf, Authentication(auth_data))
 
 
 class Request_ExportInfrastructure(IMBaseRequest):
@@ -282,7 +282,7 @@ class Request_ExportInfrastructure(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Exporting Inf."
         (inf_id, delete, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.ExportInfrastructure(inf_id, delete,
+        return IM.InfrastructureManager.InfrastructureManager.ExportInfrastructure(inf_id, delete,
                                                                                 Authentication(auth_data))
 
 
@@ -294,7 +294,7 @@ class Request_GetInfrastructureRADL(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error getting RADL of the Inf."
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetInfrastructureRADL(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetInfrastructureRADL(inf_id, Authentication(auth_data))
 
 
 class Request_GetVMContMsg(IMBaseRequest):
@@ -305,7 +305,7 @@ class Request_GetVMContMsg(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error Getting VM cont msg."
         (inf_id, vm_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetVMContMsg(inf_id, vm_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetVMContMsg(inf_id, vm_id, Authentication(auth_data))
 
 
 class Request_GetInfrastructureContMsg(IMBaseRequest):
@@ -316,7 +316,7 @@ class Request_GetInfrastructureContMsg(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error gettinf the Inf. cont msg"
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetInfrastructureContMsg(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetInfrastructureContMsg(inf_id, Authentication(auth_data))
 
 
 class Request_SaveData(IMBaseRequest):
@@ -339,7 +339,7 @@ class Request_StartVM(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error starting VM"
         (inf_id, vm_id, auth_data) = self.arguments
-        InfrastructureManager.InfrastructureManager.StartVM(
+        IM.InfrastructureManager.InfrastructureManager.StartVM(
             inf_id, vm_id, Authentication(auth_data))
         return ""
 
@@ -352,7 +352,7 @@ class Request_StopVM(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error stopping VM"
         (inf_id, vm_id, auth_data) = self.arguments
-        InfrastructureManager.InfrastructureManager.StopVM(
+        IM.InfrastructureManager.InfrastructureManager.StopVM(
             inf_id, vm_id, Authentication(auth_data))
         return ""
 
@@ -365,7 +365,7 @@ class Request_GetInfrastructureState(IMBaseRequest):
     def _call_function(self):
         self._error_mesage = "Error getting the Inf. state"
         (inf_id, auth_data) = self.arguments
-        return InfrastructureManager.InfrastructureManager.GetInfrastructureState(inf_id, Authentication(auth_data))
+        return IM.InfrastructureManager.InfrastructureManager.GetInfrastructureState(inf_id, Authentication(auth_data))
 
 
 class Request_GetVersion(IMBaseRequest):
diff --git a/IM/VirtualMachine.py b/IM/VirtualMachine.py
index a584c5775..012b52233 100644
--- a/IM/VirtualMachine.py
+++ b/IM/VirtualMachine.py
@@ -538,7 +538,7 @@ def setIps(self, public_ips, private_ips):
 
                 # Search in previous used private ips
                 private_net = None
-                for net_mask, net in private_net_map.iteritems():
+                for net_mask, net in private_net_map.items():
                     if IPAddress(private_ip) in IPNetwork(net_mask):
                         private_net = net
 
@@ -579,6 +579,7 @@ def setIps(self, public_ips, private_ips):
                 vm_system.setValue(
                     'net_interface.' + str(num_net) + '.connection', private_net.id)
 
+
     def get_ssh(self, retry=False):
         """
         Get SSH object to connect with this VM
@@ -782,7 +783,7 @@ def get_ctxt_output(self, remote_dir, delete=False):
             # And process it
             self.process_ctxt_agent_out(ctxt_agent_out)
             msg = "Contextualization agent output processed successfully"
-        except IOError, ex:
+        except IOError as ex:
             msg = "Error getting contextualization agent output " + \
                 remote_dir + "/ctxt_agent.out:  No such file."
             VirtualMachine.logger.error(msg)
@@ -804,7 +805,7 @@ def get_ctxt_output(self, remote_dir, delete=False):
                 VirtualMachine.logger.exception(
                     "Error getting stdout and stderr to guess why the agent output is not there.")
                 pass
-        except Exception, ex:
+        except Exception as ex:
             VirtualMachine.logger.exception(
                 "Error getting contextualization agent output: " + remote_dir + '/ctxt_agent.out')
             self.configured = False
@@ -845,3 +846,6 @@ def get_ssh_ansible_master(self):
             return SSHRetry(ansible_host.getHost(), user, passwd, private_key)
         else:
             return self.inf.vm_master.get_ssh(retry=True)
+
+    def __lt__(self, other):
+        return True
diff --git a/IM/ansible_utils/ansible_callbacks.py b/IM/ansible_utils/ansible_callbacks.py
index 64d3f6500..1c618352b 100644
--- a/IM/ansible_utils/ansible_callbacks.py
+++ b/IM/ansible_utils/ansible_callbacks.py
@@ -57,7 +57,7 @@ def _increment(self, what, host):
     def compute(self, runner_results, setup=False, poll=False, ignore_errors=False):
         ''' walk through all results and increment stats '''
 
-        for (host, value) in runner_results.get('contacted', {}).iteritems():
+        for (host, value) in runner_results.get('contacted', {}).items():
             if not ignore_errors and (('failed' in value and bool(value['failed'])) or
                                       ('rc' in value and value['rc'] != 0)):
                 self._increment('failures', host)
@@ -71,7 +71,7 @@ def compute(self, runner_results, setup=False, poll=False, ignore_errors=False):
                 if not poll or ('finished' in value and bool(value['finished'])):
                     self._increment('ok', host)
 
-        for (host, value) in runner_results.get('dark', {}).iteritems():
+        for (host, value) in runner_results.get('dark', {}).items():
             self._increment('dark', host)
 
     def summarize(self, host):
diff --git a/IM/ansible_utils/ansible_launcher.py b/IM/ansible_utils/ansible_launcher.py
index 921a040c6..e35fde835 100755
--- a/IM/ansible_utils/ansible_launcher.py
+++ b/IM/ansible_utils/ansible_launcher.py
@@ -34,14 +34,14 @@
     import ansible.constants as C
     from ansible import utils
 
-    from ansible_callbacks import banner, AggregateStats, PlaybookCallbacks, PlaybookRunnerCallbacks
+    from .ansible_callbacks import banner, AggregateStats, PlaybookCallbacks, PlaybookRunnerCallbacks
 else:
     from ansible.cli import CLI
     from ansible.parsing.dataloader import DataLoader
     from ansible.vars import VariableManager
     import ansible.inventory
 
-    from ansible_executor_v2 import IMPlaybookExecutor
+    from .ansible_executor_v2 import IMPlaybookExecutor
 
 
 def display(msg, color=None, stderr=False, screen_only=False, log_only=False, output=None):
@@ -127,7 +127,7 @@ def run(self):
             else:
                 display("ERROR: Unknown Ansible version.", output=self.output)
                 self.result.put((0, (1, []), output))
-        except errors.AnsibleError, e:
+        except errors.AnsibleError as e:
             display("ERROR: %s" % e, output=self.output)
             self.result.put((0, (1, []), output))
 
@@ -219,7 +219,7 @@ def launch_playbook_v2(self):
 
                 return_code = pbex.run()
 
-            except errors.AnsibleError, e:
+            except errors.AnsibleError as e:
                 display("ERROR: %s" % e, output=self.output)
                 return_code = 1
 
@@ -347,7 +347,7 @@ def launch_playbook_v1(self):
                 if len(unreachable_hosts) > 0:
                     return_code = 3
 
-            except errors.AnsibleError, e:
+            except errors.AnsibleError as e:
                 display("ERROR: %s" % e, color='red', output=self.output)
                 return_code = 1
 
diff --git a/IM/config.py b/IM/config.py
index 0d4dde0a2..a8670129f 100644
--- a/IM/config.py
+++ b/IM/config.py
@@ -14,7 +14,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import configparser
+try:
+    from ConfigParser import ConfigParser
+except ImportError:
+    from configparser import ConfigParser
 import os
 import logging
 
@@ -88,7 +91,7 @@ class Config:
     UPDATE_CTXT_LOG_INTERVAL = 20
     ANSIBLE_INSTALL_TIMEOUT = 900
 
-config = configparser.ConfigParser()
+config = ConfigParser()
 config.read([Config.IM_PATH + '/../im.cfg', Config.IM_PATH +
              '/../etc/im.cfg', '/etc/im/im.cfg'])
 
diff --git a/IM/connectors/Azure.py b/IM/connectors/Azure.py
index ffcc2d08a..32641dd77 100644
--- a/IM/connectors/Azure.py
+++ b/IM/connectors/Azure.py
@@ -17,7 +17,7 @@
 import time
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 
 try:
@@ -26,9 +26,9 @@
     from azure.mgmt.compute import ComputeManagementClient
     from azure.mgmt.network import NetworkManagementClient
     from azure.common.credentials import UserPassCredentials
-except Exception, ex:
-    print "WARN: Python Azure SDK not correctly installed. AzureCloudConnector will not work!."
-    print ex
+except Exception as ex:
+    print("WARN: Python Azure SDK not correctly installed. AzureCloudConnector will not work!.")
+    print(ex)
 
 
 class AzureCloudConnector(CloudConnector):
@@ -400,7 +400,7 @@ def create_storage_account(self, group_name, storage_account, credentials, subsc
                                                                               'location': location}
                                                                              )
             return storage_async_operation.result(), ""
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error creating the storage account")
             return None, str(ex)
 
@@ -515,7 +515,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                 self.attach_data_disks(vm, storage_account_name, credentials, subscription_id, location)
 
                 res.append((True, vm))
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error creating the VM")
                 res.append((False, "Error creating the VM: " + str(ex)))
 
@@ -561,7 +561,7 @@ def attach_data_disks(self, vm, storage_account_name, credentials, subscription_
                     }
                 )
                 async_vm_update.wait()
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error attaching disk %d to VM %s" % (cont, vm_name))
                 return False, "Error attaching disk %d to VM %s: %s" % (cont, vm_name, str(ex))
             cont += 1
@@ -578,7 +578,7 @@ def updateVMInfo(self, vm, auth_data):
             compute_client = ComputeManagementClient(credentials, subscription_id)
             # Get one the virtual machine by name
             virtual_machine = compute_client.virtual_machines.get(group_name, vm_name)
-        except Exception, ex:
+        except Exception as ex:
             if "NotFound" in str(ex):
                 vm.state = VirtualMachine.OFF
                 return (True, vm)
@@ -639,7 +639,7 @@ def finalize(self, vm, auth_data):
                 self.logger.exception("Removing RG: %s" % "rg-%s" % vm.inf.id)
                 resource_client.resource_groups.delete("rg-%s" % vm.inf.id)
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error terminating the VM")
             return False, "Error terminating the VM: " + str(ex)
 
@@ -652,7 +652,7 @@ def stop(self, vm, auth_data):
             credentials, subscription_id = self.get_credentials(auth_data)
             compute_client = ComputeManagementClient(credentials, subscription_id)
             compute_client.virtual_machines.power_off(group_name, vm_name)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error stopping the VM")
             return False, "Error stopping the VM: " + str(ex)
 
@@ -665,7 +665,7 @@ def start(self, vm, auth_data):
             credentials, subscription_id = self.get_credentials(auth_data)
             compute_client = ComputeManagementClient(credentials, subscription_id)
             compute_client.virtual_machines.start(group_name, vm_name)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error starting the VM")
             return False, "Error starting the VM: " + str(ex)
 
@@ -695,7 +695,7 @@ def alterVM(self, vm, radl, auth_data):
             async_vm_start.wait()
 
             return self.updateVMInfo(vm, auth_data)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error altering the VM")
             return False, "Error altering the VM: " + str(ex)
 
diff --git a/IM/connectors/AzureClassic.py b/IM/connectors/AzureClassic.py
index 5f824e636..6379e7b1f 100644
--- a/IM/connectors/AzureClassic.py
+++ b/IM/connectors/AzureClassic.py
@@ -22,7 +22,7 @@
 from IM.xmlobject import XMLObject
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import UserPassCredential, Feature
 from IM.config import Config
 
@@ -415,15 +415,15 @@ def get_user_cert_data(self, auth):
         if 'public_key' in auth and 'private_key' in auth:
             certificate = auth['public_key']
             fd, cert_file = tempfile.mkstemp()
-            os.write(fd, certificate)
+            os.write(fd, certificate.encode())
             os.close(fd)
-            os.chmod(cert_file, 0644)
+            os.chmod(cert_file, 0o644)
 
             private_key = auth['private_key']
             fd, key_file = tempfile.mkstemp()
-            os.write(fd, private_key)
+            os.write(fd, private_key.encode())
             os.close(fd)
-            os.chmod(key_file, 0600)
+            os.chmod(key_file, 0o600)
 
             return (cert_file, key_file)
         else:
@@ -449,10 +449,10 @@ def create_service(self, auth_data, region):
       <Description>Service %s created by the IM</Description>
       <Location>%s</Location>
     </CreateHostedService>
-            ''' % (service_name, base64.b64encode(service_name), service_name, region)
+            ''' % (service_name, base64.b64encode(service_name.encode()), service_name, region)
             headers = {'x-ms-version': '2013-03-01', 'Content-Type': 'application/xml'}
             resp = self.create_request('POST', uri, auth_data, headers, service_create_xml)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error creating the service")
             return None, "Error creating the service" + str(ex)
 
@@ -471,7 +471,7 @@ def delete_service(self, service_name, auth_data):
             uri = "/services/hostedservices/%s?comp=media" % service_name
             headers = {'x-ms-version': '2013-08-01'}
             resp = self.create_request('DELETE', uri, auth_data, headers)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error deleting the service")
             return (False, "Error deleting the service: " + str(ex))
 
@@ -556,7 +556,7 @@ def create_storage_account(self, storage_account, auth_data, region, timeout=120
             ''' % (storage_account, storage_account, base64.b64encode(storage_account), region)
             headers = {'x-ms-version': '2013-03-01', 'Content-Type': 'application/xml'}
             resp = self.create_request('POST', uri, auth_data, headers, storage_create_xml)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error creating the storage account")
             return None, "Error creating the storage account" + str(ex)
 
@@ -710,7 +710,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                         self.delete_service(service_name, auth_data)
                         res.append((False, "Error waiting the VM creation"))
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error creating the VM")
                 if service_name:
                     self.delete_service(service_name, auth_data)
@@ -780,7 +780,7 @@ def updateVMInfo(self, vm, auth_data):
             uri = "/services/hostedservices/%s/deployments/%s" % (service_name, service_name)
             headers = {'x-ms-version': '2014-02-01'}
             resp = self.create_request('GET', uri, auth_data, headers)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting the VM info: " + vm.id)
             return (False, "Error getting the VM info: " + vm.id + ". " + str(ex))
 
@@ -870,7 +870,7 @@ def call_role_operation(self, op, vm, auth_data):
 
             headers = {'x-ms-version': '2013-06-01', 'Content-Type': 'application/xml'}
             resp = self.create_request('POST', uri, auth_data, headers)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error calling role operation")
             return (False, "Error calling role operation: " + str(ex))
 
@@ -972,7 +972,7 @@ def alterVM(self, vm, radl, auth_data):
 
             headers = {'x-ms-version': '2013-11-01', 'Content-Type': 'application/xml'}
             resp = self.create_request('PUT', uri, auth_data, headers, body)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error calling update operation")
             return (False, "Error calling update operation: " + str(ex))
 
diff --git a/IM/connectors/Docker.py b/IM/connectors/Docker.py
index 4861b556c..417b14701 100644
--- a/IM/connectors/Docker.py
+++ b/IM/connectors/Docker.py
@@ -23,7 +23,7 @@
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
 from IM.config import Config
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 from IM import UnixHTTPAdapter
 
@@ -75,15 +75,15 @@ def get_user_cert_data(self, auth):
         """
         certificate = auth['cert']
         fd, cert_file = tempfile.mkstemp()
-        os.write(fd, certificate)
+        os.write(fd, certificate.encode())
         os.close(fd)
-        os.chmod(cert_file, 0644)
+        os.chmod(cert_file, 0o644)
 
         private_key = auth['key']
         fd, key_file = tempfile.mkstemp()
-        os.write(fd, private_key)
+        os.write(fd, private_key.encode())
         os.close(fd)
-        os.chmod(key_file, 0600)
+        os.chmod(key_file, 0o600)
 
         return (cert_file, key_file)
 
@@ -330,7 +330,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
 
                 res.append((True, vm))
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error connecting with Docker server")
                 res.append((False, "ERROR: " + str(ex)))
 
@@ -357,7 +357,7 @@ def updateVMInfo(self, vm, auth_data):
             self.setIPs(vm, output)
             return (True, vm)
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error connecting with Docker server")
             self.logger.error(ex)
             return (False, "Error connecting with Docker server")
diff --git a/IM/connectors/Dummy.py b/IM/connectors/Dummy.py
index 6e6a5b6f7..f3674fd18 100644
--- a/IM/connectors/Dummy.py
+++ b/IM/connectors/Dummy.py
@@ -16,7 +16,7 @@
 
 import time
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 
 
diff --git a/IM/connectors/EC2.py b/IM/connectors/EC2.py
index a2832909d..23b3c5635 100644
--- a/IM/connectors/EC2.py
+++ b/IM/connectors/EC2.py
@@ -21,13 +21,13 @@
 try:
     import boto.ec2
     import boto.vpc
-except Exception, ex:
-    print "WARN: Boto library not correctly installed. EC2CloudConnector will not work!."
-    print ex
+except Exception as ex:
+    print("WARN: Boto library not correctly installed. EC2CloudConnector will not work!.")
+    print(ex)
 
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 
 
@@ -184,7 +184,7 @@ def get_connection(self, region_name, auth_data):
                     raise Exception("No correct auth data has been specified to EC2: "
                                     "username (Access Key) and password (Secret Key)")
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception(
                     "Error getting the region " + region_name)
                 raise Exception("Error getting the region " +
@@ -338,7 +338,7 @@ def create_security_group(self, conn, inf, radl, vpc=None):
                 try:
                     sg = conn.create_security_group(
                         sg_name, "Security group created by the IM", vpc_id=vpc)
-                except Exception, crex:
+                except Exception as crex:
                     # First check if the SG does exist
                     sg = self._get_security_group(conn, sg_name)
                     if not sg:
@@ -378,12 +378,12 @@ def create_security_group(self, conn, inf, radl, vpc=None):
                 sg.authorize('tcp', 0, 65535, src_group=sg)
                 sg.authorize('udp', 0, 65535, src_group=sg)
                 # sg.authorize('icmp', 0, 65535, src_group=sg)
-            except Exception, addex:
+            except Exception as addex:
                 self.logger.warn(
                     "Exception adding SG rules. Probably the rules exists:" + str(addex))
                 pass
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error Creating the Security group")
             if vpc:
                 raise Exception(
@@ -418,7 +418,7 @@ def create_keypair(self, system, conn):
                 keypair = conn.create_key_pair(keypair_name)
                 created = True
                 keypair.save(self.KEYPAIR_DIR)
-                os.chmod(keypair_file, 0400)
+                os.chmod(keypair_file, 0o400)
                 with open(keypair_file, "r") as fkeypair:
                     system.setUserKeyCredentials(system.getCredentials().username,
                                                  None, fkeypair.read())
@@ -500,7 +500,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
             return res
         else:
             block_device_name = None
-            for name, device in image.block_device_mapping.iteritems():
+            for name, device in image.block_device_mapping.items():
                 if device.snapshot_id or device.volume_id:
                     block_device_name = name
 
@@ -676,7 +676,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                                 res.append(
                                     (False, "Error launching the image"))
 
-                except Exception, ex:
+                except Exception as ex:
                     self.logger.exception("Error launching instance.")
                     res.append(
                         (False, "Error launching the instance: " + str(ex)))
@@ -791,7 +791,7 @@ def delete_volumes(self, conn, volumes, instance_id, timeout=240):
                     else:
                         self.logger.debug(
                             "State: " + str(curr_vol.attachment_state()))
-                except Exception, ex:
+                except Exception as ex:
                     self.logger.warn("Error removing the volume: " + str(ex))
 
                 if not deleted:
@@ -1039,7 +1039,7 @@ def updateVMInfo(self, vm, auth_data):
                         im_username = auth_data.getAuthInfo(
                             'InfrastructureManager')[0]['username']
                     instance.add_tag("IM-USER", im_username)
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception(
                     "Error updating the instance " + instance_id)
                 return (False, "Error updating the instance " + instance_id + ": " + str(ex))
@@ -1063,7 +1063,7 @@ def updateVMInfo(self, vm, auth_data):
             try:
                 vm.info.systems[0].setValue('launch_time', int(time.mktime(
                     time.strptime(instance.launch_time[:19], '%Y-%m-%dT%H:%M:%S'))))
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.warn(
                     "Error setting the launch_time of the instance. Probably the instance is not running:" + str(ex))
 
@@ -1177,7 +1177,7 @@ def delete_security_group(self, conn, inf, timeout=90):
                         sg.revoke('tcp', 0, 65535, src_group=sg)
                         sg.revoke('udp', 0, 65535, src_group=sg)
                         time.sleep(2)
-                    except Exception, ex:
+                    except Exception as ex:
                         self.logger.warn(
                             "Error revoking self rules: " + str(ex))
 
@@ -1188,7 +1188,7 @@ def delete_security_group(self, conn, inf, timeout=90):
                         try:
                             sg.delete()
                             deleted = True
-                        except Exception, ex:
+                        except Exception as ex:
                             # Check if it has been deleted yet
                             sg = self._get_security_group(conn, sg_name)
                             if not sg:
diff --git a/IM/connectors/FogBow.py b/IM/connectors/FogBow.py
index 5423a4501..0ff597506 100644
--- a/IM/connectors/FogBow.py
+++ b/IM/connectors/FogBow.py
@@ -17,10 +17,15 @@
 import json
 import os
 import sys
-import httplib
+
+try:
+    from httplib import HTTPSConnection, HTTPConnection
+except ImportError:
+    from http.client import HTTPSConnection, HTTPConnection
+
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 
 
@@ -59,9 +64,9 @@ def get_http_connection(self):
         """
 
         if self.cloud.protocol == 'https':
-            conn = httplib.HTTPSConnection(self.cloud.server, self.cloud.port)
+            conn = HTTPSConnection(self.cloud.server, self.cloud.port)
         else:
-            conn = httplib.HTTPConnection(self.cloud.server, self.cloud.port)
+            conn = HTTPConnection(self.cloud.server, self.cloud.port)
 
         return conn
 
@@ -264,7 +269,7 @@ def updateVMInfo(self, vm, auth_data):
 
                         return (True, vm)
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error connecting with FogBow Manager")
             return (False, "Error connecting with FogBow Manager: " + str(ex))
 
@@ -301,7 +306,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                 conn.putheader('Content-Type', 'text/occi')
                 # conn.putheader('Accept', 'text/occi')
                 if auth_headers:
-                    for k, v in auth_headers.iteritems():
+                    for k, v in auth_headers.items():
                         conn.putheader(k, v)
 
                 conn.putheader(
@@ -363,7 +368,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                     vm.info.systems[0].setValue('instance_id', str(vm.id))
                     res.append((True, vm))
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error connecting with FogBow manager")
                 res.append((False, "ERROR: " + str(ex)))
 
@@ -446,7 +451,7 @@ def getIdentityPlugin(identity_type):
             raise Exception("Not valid Identity Plugin.")
         try:
             return getattr(sys.modules[__name__], identity_type + "IdentityPlugin")()
-        except Exception, ex:
+        except Exception as ex:
             raise Exception("IdentityPlugin not supported: %s (error: %s)" % (
                 identity_type, str(ex)))
 
@@ -499,7 +504,7 @@ def create_token(params):
                 server = uri[1].split(":")[0]
                 port = int(uri[1].split(":")[1])
 
-                conn = httplib.HTTPSConnection(server, port)
+                conn = HTTPSConnection(server, port)
                 conn.putrequest('POST', "/v2.0/tokens")
                 conn.putheader('Accept', 'application/json')
                 conn.putheader('Content-Type', 'application/json')
diff --git a/IM/connectors/GCE.py b/IM/connectors/GCE.py
index 5ab34e31f..56ec3de94 100644
--- a/IM/connectors/GCE.py
+++ b/IM/connectors/GCE.py
@@ -22,11 +22,11 @@
     from libcloud.compute.types import NodeState, Provider
     from libcloud.compute.providers import get_driver
     from libcloud.common.google import ResourceNotFoundError
-except Exception, ex:
-    print "WARN: libcloud library not correctly installed. GCECloudConnector will not work!."
-    print ex
+except Exception as ex:
+    print("WARN: libcloud library not correctly installed. GCECloudConnector will not work!.")
+    print(ex)
 
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
 from radl.radl import Feature
@@ -338,7 +338,7 @@ def create_firewall(self, inf, net_name, radl, driver):
 
                     try:
                         driver.ex_create_firewall(firewall_name, allowed, network=net_name)
-                    except Exception, addex:
+                    except Exception as addex:
                         self.logger.warn("Exception creating FW: " + str(addex))
                         pass
 
@@ -443,7 +443,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
     def finalize(self, vm, auth_data):
         try:
             node = self.get_node_with_id(vm.id, auth_data)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting VM: %s. Err: %s." % (vm.id, str(ex)))
             return (False, "Error getting VM: %s. Err: %s." % (vm.id, str(ex)))
 
@@ -617,7 +617,7 @@ def updateVMInfo(self, vm, auth_data):
             node = driver.ex_get_node(vm.id)
         except ResourceNotFoundError:
             self.logger.warn("VM " + str(vm.id) + " does not exist.")
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting VM info: %s" % vm.id)
             return (False, "Error getting VM info: %s. %s" % (vm.id, str(ex)))
 
@@ -656,13 +656,13 @@ def start(self, vm, auth_data):
             node = driver.ex_get_node(vm.id)
         except ResourceNotFoundError:
             return (False, "VM " + str(vm.id) + " does not exist.")
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting VM %s" % vm.id)
             return (False, "Error getting VM %s: %s" % (vm.id, str(ex)))
 
         try:
             driver.ex_start_node(node)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error starting VM %s" % vm.id)
             return (False, "Error starting VM %s: %s" % (vm.id, str(ex)))
 
@@ -675,13 +675,13 @@ def stop(self, vm, auth_data):
             node = driver.ex_get_node(vm.id)
         except ResourceNotFoundError:
             return (False, "VM " + str(vm.id) + " does not exist.")
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting VM %s" % vm.id)
             return (False, "Error getting VM %s: %s" % (vm.id, str(ex)))
 
         try:
             driver.ex_stop_node(node)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error stopping VM %s" % vm.id)
             return (False, "Error stopping VM %s: %s" % (vm.id, str(ex)))
 
diff --git a/IM/connectors/Kubernetes.py b/IM/connectors/Kubernetes.py
index d3d43e646..c98b7bd87 100644
--- a/IM/connectors/Kubernetes.py
+++ b/IM/connectors/Kubernetes.py
@@ -21,7 +21,7 @@
 import requests
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 from IM.config import Config
 
@@ -366,7 +366,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
 
                     res.append((True, vm))
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception(
                     "Error connecting with Kubernetes API server")
                 res.append((False, "ERROR: " + str(ex)))
@@ -388,7 +388,7 @@ def _get_pod(self, vm_id, auth_data):
             else:
                 return (False, resp.status, resp.text)
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception(
                 "Error connecting with Kubernetes API server")
             return (False, None, "Error connecting with Kubernetes API server: " + str(ex))
@@ -521,7 +521,7 @@ def alterVM(self, vm, radl, auth_data):
                         Feature("memory.size", "=", new_memory, 'B'), conflict="other", missing="other")
                 return (True, self.updateVMInfo(vm, auth_data))
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception(
                 "Error connecting with Kubernetes API server")
             return (False, "ERROR: " + str(ex))
diff --git a/IM/connectors/LibCloud.py b/IM/connectors/LibCloud.py
index 54d78b241..416d36564 100644
--- a/IM/connectors/LibCloud.py
+++ b/IM/connectors/LibCloud.py
@@ -20,13 +20,13 @@
     from libcloud.compute.base import NodeImage, NodeAuthSSHKey
     from libcloud.compute.types import Provider, NodeState
     from libcloud.compute.providers import get_driver
-except Exception, ex:
-    print "WARN: libcloud library not correctly installed. LibCloudCloudConnector will not work!."
-    print ex
+except Exception as ex:
+    print("WARN: libcloud library not correctly installed. LibCloudCloudConnector will not work!.")
+    print(ex)
 
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 
 
@@ -61,7 +61,7 @@ def get_driver(self, auth_data):
                 MAP = {"username": "key", "password": "secret"}
 
                 params = {}
-                for key, value in auth[0].iteritems():
+                for key, value in auth[0].items():
                     if key not in ["type", "driver", "id"]:
                         params[MAP[key]] = value
 
@@ -530,7 +530,7 @@ def alterVM(self, vm, radl, auth_data):
 
                 try:
                     success = resize_func(node, instance_type)
-                except Exception, ex:
+                except Exception as ex:
                     self.logger.exception("Error resizing VM.")
                     return (False, "Error resizing VM: " + str(ex))
 
diff --git a/IM/connectors/OCCI.py b/IM/connectors/OCCI.py
index b3045f76f..c0181eea3 100644
--- a/IM/connectors/OCCI.py
+++ b/IM/connectors/OCCI.py
@@ -24,7 +24,7 @@
 import tempfile
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import Feature
 from netaddr import IPNetwork, IPAddress
 from IM.config import Config
@@ -57,7 +57,7 @@ def create_request_static(method, url, auth, headers, body=None):
             proxy = auth['proxy']
 
             (fproxy, proxy_filename) = tempfile.mkstemp()
-            os.write(fproxy, proxy)
+            os.write(fproxy, proxy.encode())
             os.close(fproxy)
             cert = proxy_filename
         else:
@@ -344,7 +344,7 @@ def updateVMInfo(self, vm, auth_data):
                 self.set_disk_info(vm, resp.text, auth_data)
                 return (True, vm)
 
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error connecting with OCCI server")
             return (False, "Error connecting with OCCI server: " + str(ex))
 
@@ -526,7 +526,7 @@ def get_volume_info(self, storage_id, auth_data):
                 return (False, resp.reason + "\n" + resp.text)
             else:
                 return (True, resp.text)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error getting volume info")
             return False, str(ex)
 
@@ -553,7 +553,7 @@ def create_volume(self, size, name, auth_data):
             else:
                 occi_id = os.path.basename(resp.text)
                 return True, occi_id
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error creating volume")
             return False, str(ex)
 
@@ -643,9 +643,9 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
         if public_key:
             # Add user cloud init data
             cloud_config_str = self.get_cloud_init_data(radl)
-            cloud_config = self.gen_cloud_config(public_key, user, cloud_config_str)
-            user_data = base64.b64encode(cloud_config).replace("\n", "")
-            self.logger.debug("Cloud init: " + cloud_config)
+            cloud_config = self.gen_cloud_config(public_key, user, cloud_config_str).encode()
+            user_data = str(base64.b64encode(cloud_config)).replace("\n", "")
+            self.logger.debug("Cloud init: %s" % cloud_config)
 
         # Get the info about the OCCI server (GET /-/)
         occi_info = self.query_occi(auth_data)
@@ -751,7 +751,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
                     else:
                         res.append((False, 'Unknown Error launching the VM.'))
 
-            except Exception, ex:
+            except Exception as ex:
                 self.logger.exception("Error connecting with OCCI server")
                 res.append((False, "ERROR: " + str(ex)))
                 for _, volume_id in volumes:
@@ -791,7 +791,7 @@ def get_attached_volumes(self, vm, auth_data):
                     if not device.endswith("vda") and not device.endswith("hda"):
                         deleted_vols.append((link, num_storage, device))
                 return (True, deleted_vols)
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error deleting volumes")
             return (False, "Error deleting volumes " + str(ex))
 
@@ -922,7 +922,7 @@ def alterVM(self, vm, radl, auth_data):
                 else:
                     return (False, "Error creating the new volume: " + volume_id)
                 cont += 1
-        except Exception, ex:
+        except Exception as ex:
             self.logger.exception("Error connecting with OCCI server")
             return (False, "Error connecting with OCCI server: " + str(ex))
 
@@ -989,7 +989,7 @@ def get_keystone_uri(occi, auth_data):
                 return www_auth_head.split('=')[1].replace("'", "")
             else:
                 return None
-        except SSLError, ex:
+        except SSLError as ex:
             occi.logger.exception(
                 "Error with the credentials when contacting with the OCCI server.")
             raise Exception(
@@ -1064,6 +1064,6 @@ def get_keystone_token(occi, keystone_uri, auth):
                     break
 
             return tenant_token_id
-        except Exception, ex:
+        except Exception as ex:
             occi.logger.exception("Error obtaining Keystone Token.")
             raise Exception("Error obtaining Keystone Token: %s" % str(ex))
diff --git a/IM/connectors/OpenNebula.py b/IM/connectors/OpenNebula.py
index b47ab3ad8..3530ca79a 100644
--- a/IM/connectors/OpenNebula.py
+++ b/IM/connectors/OpenNebula.py
@@ -15,13 +15,17 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import hashlib
-import xmlrpclib
+try:
+    from xmlrpclib import ServerProxy
+except ImportError:
+    from xmlrpc.client import ServerProxy
+
 import time
 
 from IM.xmlobject import XMLObject
 from IM.uriparse import uriparse
 from IM.VirtualMachine import VirtualMachine
-from CloudConnector import CloudConnector
+from .CloudConnector import CloudConnector
 from radl.radl import network, Feature
 from IM.config import ConfigOpenNebula
 from netaddr import IPNetwork, IPAddress
@@ -203,7 +207,7 @@ def getSessionID(self, auth_data, hash_password=None):
             auth = auths[0]
 
         if 'username' in auth and 'password' in auth:
-            passwd = auth['password']
+            passwd = auth['password'].encode('utf-8')
             if hash_password is None:
                 one_ver = self.getONEVersion(auth_data)
                 if one_ver == "2.0.0" or one_ver == "3.0.0":
@@ -211,7 +215,7 @@ def getSessionID(self, auth_data, hash_password=None):
             if hash_password:
                 passwd = hashlib.sha1(passwd.strip()).hexdigest()
 
-            return auth['username'] + ":" + passwd
+            return auth['username'] + ":" + str(passwd)
         else:
             raise Exception("No correct auth data has been specified to OpenNebula: username and password")
 
@@ -254,7 +258,7 @@ def setIPsFromTemplate(self, vm, template):
                 i += 1
 
     def updateVMInfo(self, vm, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
 
         session_id = self.getSessionID(auth_data)
         if session_id is None:
@@ -318,7 +322,7 @@ def updateVMInfo(self, vm, auth_data):
             return (success, res_info)
 
     def launch(self, inf, radl, requested_radl, num_vm, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return [(False, "Incorrect auth data, username and password must be specified for OpenNebula provider.")]
@@ -352,7 +356,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
         return res
 
     def finalize(self, vm, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return (False, "Incorrect auth data, username and password must be specified for OpenNebula provider.")
@@ -371,7 +375,7 @@ def finalize(self, vm, auth_data):
         return (success, err)
 
     def stop(self, vm, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return (False, "Incorrect auth data, username and password must be specified for OpenNebula provider.")
@@ -390,7 +394,7 @@ def stop(self, vm, auth_data):
         return (success, err)
 
     def start(self, vm, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return (False, "Incorrect auth data, username and password must be specified for OpenNebula provider.")
@@ -511,7 +515,7 @@ def getONEVersion(self, auth_data):
 
          Returns: str with the ONE version (format: X.X.X)
         """
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
 
         version = "2.0.0"
         methods = server.system.listMethods()
@@ -591,7 +595,7 @@ def getONENetworks(self, auth_data):
          Returns: a list of tuples (net_name, net_id, is_public) with the name, ID, and boolean specifying
          if it is a public network of the found network None if not found
         """
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return None
@@ -795,7 +799,7 @@ def checkResize(self):
 
          Returns: bool, True if the one.vm.resize function appears in the ONE server or false otherwise
         """
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
 
         methods = server.system.listMethods()
         if "one.vm.resize" in methods:
@@ -807,7 +811,7 @@ def poweroff(self, vm, auth_data, timeout=60):
         """
         Poweroff the VM and waits for it to be in poweredoff state
         """
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
         session_id = self.getSessionID(auth_data)
         if session_id is None:
             return (False, "Incorrect auth data, username and password must be specified for OpenNebula provider.")
@@ -874,7 +878,7 @@ def alterVM(self, vm, radl, auth_data):
             return (True, "")
 
     def attach_volume(self, vm, disk_size, disk_device, disk_fstype, session_id):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
 
         disk_temp = '''
             DISK = [
@@ -932,7 +936,7 @@ def attach_new_disks(self, vm, system, session_id):
         return (True, "")
 
     def alter_mem_cpu(self, vm, system, session_id, auth_data):
-        server = xmlrpclib.ServerProxy(self.server_url, allow_none=True)
+        server = ServerProxy(self.server_url, allow_none=True)
 
         cpu = vm.info.systems[0].getValue('cpu.count')
         memory = vm.info.systems[0].getFeature('memory.size').getValue('M')
diff --git a/IM/connectors/OpenStack.py b/IM/connectors/OpenStack.py
index e503b0d0a..cca8d0481 100644
--- a/IM/connectors/OpenStack.py
+++ b/IM/connectors/OpenStack.py
@@ -21,9 +21,9 @@
     from libcloud.compute.types import Provider, NodeState
     from libcloud.compute.providers import get_driver
     from libcloud.compute.base import NodeImage, NodeAuthSSHKey
-except Exception, ex:
-    print "WARN: libcloud library not correctly installed. OpenStackCloudConnector will not work!."
-    print ex
+except Exception as ex:
+    print("WARN: libcloud library not correctly installed. OpenStackCloudConnector will not work!.")
+    print(ex)
 
 from IM.connectors.LibCloud import LibCloudCloudConnector
 from IM.config import Config
@@ -430,7 +430,7 @@ def launch(self, inf, radl, requested_radl, num_vm, auth_data):
             msg = "Error creating the node. "
             try:
                 node = driver.create_node(**args)
-            except Exception, ex:
+            except Exception as ex:
                 msg += str(ex)
 
             if node:
@@ -628,7 +628,7 @@ def create_security_group(self, driver, inf, radl):
                         try:
                             driver.ex_create_security_group_rule(
                                 sg, protocol, remote_port, remote_port, '0.0.0.0/0')
-                        except Exception, ex:
+                        except Exception as ex:
                             self.logger.warn(
                                 "Exception adding SG rules: " + str(ex))
 
@@ -640,7 +640,7 @@ def create_security_group(self, driver, inf, radl):
                 sg, 'tcp', 1, 65535, source_security_group=sg)
             driver.ex_create_security_group_rule(
                 sg, 'udp', 1, 65535, source_security_group=sg)
-        except Exception, addex:
+        except Exception as addex:
             self.logger.warn(
                 "Exception adding SG rules. Probably the rules exists:" + str(addex))
             pass
@@ -713,7 +713,7 @@ def delete_security_group(self, node, sgs, inf, vm_id, timeout=60):
                     try:
                         node.driver.ex_delete_security_group(sg)
                         deleted = True
-                    except Exception, ex:
+                    except Exception as ex:
                         # Check if it has been deleted yet
                         sg = self._get_security_group(node.driver, sg.name)
                         if not sg:
diff --git a/IM/db.py b/IM/db.py
index abcb01b15..e5d10c155 100644
--- a/IM/db.py
+++ b/IM/db.py
@@ -148,7 +148,7 @@ def _execute_retry(self, sql, args, fetch=False):
                         res = True
                     return res
                 # If the operational error is db lock, retry
-                except sqlite.OperationalError, ex:
+                except sqlite.OperationalError as ex:
                     if str(ex).lower() == 'database is locked':
                         retries_cont += 1
                         # release the connection
@@ -158,7 +158,7 @@ def _execute_retry(self, sql, args, fetch=False):
                         self.connect()
                     else:
                         raise ex
-                except sqlite.IntegrityError, ex:
+                except sqlite.IntegrityError as ex:
                     raise IntegrityError()
 
     def execute(self, sql, args=None):
diff --git a/IM/ganglia.py b/IM/ganglia.py
index 526ee3cdf..469643f49 100644
--- a/IM/ganglia.py
+++ b/IM/ganglia.py
@@ -15,7 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import socket
-from xmlobject import XMLObject
+from IM.xmlobject import XMLObject
 
 
 class EXTRA_ELEMENT(XMLObject):
@@ -70,7 +70,7 @@ def update_ganglia_info(inf):
                 s.settimeout(2)
                 if(s.connect_ex((master_ip, ganglia_info.ganglia_port)) == 0):
                     port_open = True
-            except Exception, ex:
+            except Exception as ex:
                 return (False, "Error connecting to ganglia: " + str(ex))
         else:
             return (False, "VM master without public IP")
@@ -137,7 +137,7 @@ def update_ganglia_info(inf):
                                         vm.info.systems[0].setValue(
                                             "swap", float_val, metric.UNITS)
 
-        except Exception, ex:
+        except Exception as ex:
             return (False, "Error getting ganglia information: " + str(ex))
 
         return (True, "")
diff --git a/IM/recipe.py b/IM/recipe.py
index 02818869d..cff5daee7 100644
--- a/IM/recipe.py
+++ b/IM/recipe.py
@@ -14,9 +14,9 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from db import DataBase
+from IM.db import DataBase
 
-from config import Config
+from IM.config import Config
 from radl.radl import FeaturesApp
 
 
diff --git a/IM/request.py b/IM/request.py
index c65d3ee56..8807445b5 100644
--- a/IM/request.py
+++ b/IM/request.py
@@ -15,11 +15,22 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 import sys
-from queue import Queue, Empty
 import threading
-from xmlrpc.server import SimpleXMLRPCServer
-import socketserver
 import time
+
+try:
+    from Queue import Queue, Empty
+except ImportError:
+    from queue import Queue, Empty
+try:
+    from SimpleXMLRPCServer import SimpleXMLRPCServer
+except ImportError:
+    from xmlrpc.server import SimpleXMLRPCServer
+try:
+    from SocketServer import ThreadingMixIn
+except ImportError:
+    from socketserver import ThreadingMixIn
+
 from IM.timedcall import TimedCall
 from IM.config import Config
 
@@ -248,7 +259,7 @@ def process(self):
         self.__thread.start()
 
 
-class AsyncXMLRPCServer(socketserver.ThreadingMixIn, SimpleXMLRPCServer):
+class AsyncXMLRPCServer(ThreadingMixIn, SimpleXMLRPCServer):
 
     def serve_forever_in_thread(self):
         """
@@ -266,7 +277,7 @@ def serve_forever_in_thread(self):
 if Config.XMLRCP_SSL:
     from springpython.remoting.xmlrpc import SSLServer
 
-    class AsyncSSLXMLRPCServer(socketserver.ThreadingMixIn, SSLServer):
+    class AsyncSSLXMLRPCServer(ThreadingMixIn, SSLServer):
 
         def __init__(self, *args, **kwargs):
             super(AsyncSSLXMLRPCServer, self).__init__(*args, **kwargs)
diff --git a/IM/retry.py b/IM/retry.py
index 87a655ad4..75c0da672 100644
--- a/IM/retry.py
+++ b/IM/retry.py
@@ -31,14 +31,14 @@ def f_retry(*args, **kwargs):
             while mtries > 1:
                 try:
                     return f(*args, **kwargs)
-                except ExceptionToCheck, e:
+                except ExceptionToCheck as e:
                     if not quiet:
                         msg = "%s, Retrying in %d seconds..." % (
                             str(e), mdelay)
                         if logger:
                             logger.warning(msg)
                         else:
-                            print msg
+                            print(msg)
                     time.sleep(mdelay)
                     mtries -= 1
                     mdelay *= backoff
diff --git a/setup.py b/setup.py
index 16b786782..5a81f2535 100644
--- a/setup.py
+++ b/setup.py
@@ -58,5 +58,6 @@
       install_requires=["ansible >= 1.8", "paramiko >= 1.14", "PyYAML", "suds-py3",
                         "boto >= 2.29", "apache-libcloud >= 0.17", "RADL", "bottle", "netaddr", "requests",
                         "scp", "cherrypy", "mysqlclient",
-                        "azure-common", "azure-mgmt-storage", "azure-mgmt-compute", "azure-mgmt-network", "azure-mgmt-resource"]
+                        "azure-common", "msrest", "msrestazure", "azure-mgmt-storage",
+                        "azure-mgmt-compute", "azure-mgmt-network", "azure-mgmt-resource"]
       )
diff --git a/test/functional/test_im.py b/test/functional/test_im.py
index a46c7935b..97198b32a 100755
--- a/test/functional/test_im.py
+++ b/test/functional/test_im.py
@@ -54,9 +54,9 @@ def __init__(self, *args):
 
     def setUp(self):
 
+        Config.DATA_DB = "/tmp/inf.dat"
+        InfrastructureList.load_data()
         IM._reinit()
-        # Patch save_data
-        IM.save_data = staticmethod(lambda *args: None)
 
         ch = logging.StreamHandler(sys.stdout)
         log = logging.getLogger('InfrastructureManager')
diff --git a/test/integration/QuickTestIM.py b/test/integration/QuickTestIM.py
index 2ad3b0c34..9c243762c 100755
--- a/test/integration/QuickTestIM.py
+++ b/test/integration/QuickTestIM.py
@@ -148,7 +148,7 @@ def test_12_getradl(self):
             success, msg="ERROR calling GetInfrastructureRADL: " + str(res))
         try:
             radl_parse.parse_radl(res)
-        except Exception, ex:
+        except Exception as ex:
             self.assertTrue(
                 False, msg="ERROR parsing the RADL returned by GetInfrastructureRADL: " + str(ex))
 
@@ -186,7 +186,7 @@ def test_15_get_vm_info(self):
         self.assertTrue(success, msg="ERROR calling GetVMInfo: " + str(info))
         try:
             radl_parse.parse_radl(info)
-        except Exception, ex:
+        except Exception as ex:
             self.assertTrue(
                 False, msg="ERROR parsing the RADL returned by GetVMInfo: " + str(ex))
 
@@ -254,7 +254,7 @@ def test_20_getstate(self):
         vm_states = res['vm_states']
         self.assertEqual(len(vm_states), 3, msg="ERROR getting infrastructure state: Incorrect number of VMs(" +
                          str(len(vm_states)) + "). It must be 3")
-        for vm_id, vm_state in vm_states.iteritems():
+        for vm_id, vm_state in vm_states.items():
             self.assertEqual(vm_state, "configured", msg="Unexpected vm state: " +
                              vm_state + " in VM ID " + str(vm_id) + ". It must be 'configured'.")
 
diff --git a/test/integration/TestIM.py b/test/integration/TestIM.py
index 95430f9b3..5cd5df2a8 100755
--- a/test/integration/TestIM.py
+++ b/test/integration/TestIM.py
@@ -156,7 +156,7 @@ def test_12_getradl(self):
             success, msg="ERROR calling GetInfrastructureRADL: " + str(res))
         try:
             radl_parse.parse_radl(res)
-        except Exception, ex:
+        except Exception as ex:
             self.assertTrue(
                 False, msg="ERROR parsing the RADL returned by GetInfrastructureRADL: " + str(ex))
 
@@ -194,7 +194,7 @@ def test_15_get_vm_info(self):
         self.assertTrue(success, msg="ERROR calling GetVMInfo: " + str(info))
         try:
             radl_parse.parse_radl(info)
-        except Exception, ex:
+        except Exception as ex:
             self.assertTrue(
                 False, msg="ERROR parsing the RADL returned by GetVMInfo: " + str(ex))
 
@@ -261,7 +261,7 @@ def test_20_getstate(self):
         vm_states = res['vm_states']
         self.assertEqual(len(vm_states), 4, msg="ERROR getting infrastructure state: Incorrect number of VMs(" +
                          str(len(vm_states)) + "). It must be 4")
-        for vm_id, vm_state in vm_states.iteritems():
+        for vm_id, vm_state in vm_states.items():
             self.assertEqual(vm_state, "configured", msg="Unexpected vm state: " +
                              vm_state + " in VM ID " + str(vm_id) + ". It must be 'configured'.")
 
diff --git a/test/integration/TestREST.py b/test/integration/TestREST.py
index 28c11d794..16a0af9a6 100755
--- a/test/integration/TestREST.py
+++ b/test/integration/TestREST.py
@@ -276,7 +276,7 @@ def test_34_get_radl(self):
                          msg="ERROR getting the infrastructure RADL:" + output)
         try:
             radl_parse.parse_radl(output)
-        except Exception, ex:
+        except Exception as ex:
             self.assertTrue(
                 False, msg="ERROR parsing the RADL returned by GetInfrastructureRADL: " + str(ex))
 
@@ -340,7 +340,7 @@ def test_45_getstate(self):
         vm_states = res['state']['vm_states']
         self.assertEqual(state, "configured", msg="Unexpected inf state: " +
                          state + ". It must be 'configured'.")
-        for vm_id, vm_state in vm_states.iteritems():
+        for vm_id, vm_state in vm_states.items():
             self.assertEqual(vm_state, "configured", msg="Unexpected vm state: " +
                              vm_state + " in VM ID " + str(vm_id) + ". It must be 'configured'.")
 
diff --git a/test/loadtest/LoadTestREST.py b/test/loadtest/LoadTestREST.py
index b9874f65e..020dcae83 100755
--- a/test/loadtest/LoadTestREST.py
+++ b/test/loadtest/LoadTestREST.py
@@ -403,7 +403,7 @@ def test_45_getstate(self):
         vm_states = res['state']['vm_states']
         self.assertEqual(state, "configured", msg="Unexpected inf state: " +
                          state + ". It must be 'configured'.")
-        for vm_id, vm_state in vm_states.iteritems():
+        for vm_id, vm_state in vm_states.items():
             self.assertEqual(vm_state, "configured", msg="Unexpected vm state: " +
                              vm_state + " in VM ID " + str(vm_id) + ". It must be 'configured'.")
 
diff --git a/test/unit/SSH.py b/test/unit/SSH.py
index e9ec4c560..d3f69ae90 100755
--- a/test/unit/SSH.py
+++ b/test/unit/SSH.py
@@ -176,7 +176,7 @@ def test_sftp_chmod(self, from_transport, ssh_client):
         client = MagicMock()
         from_transport.return_value = client
 
-        res = ssh.sftp_chmod("some_file", 0644)
+        res = ssh.sftp_chmod("some_file", 0o644)
         self.assertTrue(res)
 
 
diff --git a/test/unit/connectors/Azure.py b/test/unit/connectors/Azure.py
index 0422fb78f..5a7c077d5 100755
--- a/test/unit/connectors/Azure.py
+++ b/test/unit/connectors/Azure.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/AzureClassic.py b/test/unit/connectors/AzureClassic.py
index b43bd59a5..498d6036f 100644
--- a/test/unit/connectors/AzureClassic.py
+++ b/test/unit/connectors/AzureClassic.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/Docker.py b/test/unit/connectors/Docker.py
index ccf1f7297..83b316d55 100755
--- a/test/unit/connectors/Docker.py
+++ b/test/unit/connectors/Docker.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/EC2.py b/test/unit/connectors/EC2.py
index 12cddc764..f7f7f792a 100755
--- a/test/unit/connectors/EC2.py
+++ b/test/unit/connectors/EC2.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/Fogbow.py b/test/unit/connectors/Fogbow.py
index 1bec7c10a..c19e56334 100755
--- a/test/unit/connectors/Fogbow.py
+++ b/test/unit/connectors/Fogbow.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
@@ -126,7 +129,7 @@ def get_response(self):
     def request(self, method, url, body=None, headers={}):
         self.__class__.last_op = method, url
 
-    @patch('httplib.HTTPConnection')
+    @patch('IM.connectors.FogBow.HTTPConnection')
     def test_20_launch(self, connection):
         radl_data = """
             network net1 (outbound = 'yes' and outports = '8080')
@@ -164,7 +167,7 @@ def test_20_launch(self, connection):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('httplib.HTTPConnection')
+    @patch('IM.connectors.FogBow.HTTPConnection')
     def test_30_updateVMInfo(self, connection):
         radl_data = """
             network net (outbound = 'yes')
@@ -201,7 +204,7 @@ def test_30_updateVMInfo(self, connection):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('httplib.HTTPConnection')
+    @patch('IM.connectors.FogBow.HTTPConnection')
     def test_60_finalize(self, connection):
         auth = Authentication([{'id': 'fogbow', 'type': 'FogBow', 'proxy': 'user', 'host': 'server.com:8182'}])
         fogbow_cloud = self.get_fogbow_cloud()
diff --git a/test/unit/connectors/GCE.py b/test/unit/connectors/GCE.py
index 2d2b35ed2..9a2d451b7 100755
--- a/test/unit/connectors/GCE.py
+++ b/test/unit/connectors/GCE.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/Kubernetes.py b/test/unit/connectors/Kubernetes.py
index 6941eece1..0a4002cb5 100755
--- a/test/unit/connectors/Kubernetes.py
+++ b/test/unit/connectors/Kubernetes.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/LibCloud.py b/test/unit/connectors/LibCloud.py
index d30da9ced..3994bda21 100755
--- a/test/unit/connectors/LibCloud.py
+++ b/test/unit/connectors/LibCloud.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/OCCI.py b/test/unit/connectors/OCCI.py
index 0398e524e..34fbd27d0 100755
--- a/test/unit/connectors/OCCI.py
+++ b/test/unit/connectors/OCCI.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/connectors/OpenNebula.py b/test/unit/connectors/OpenNebula.py
index dc5eae7d6..cad112df4 100755
--- a/test/unit/connectors/OpenNebula.py
+++ b/test/unit/connectors/OpenNebula.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
@@ -99,7 +102,7 @@ def test_10_concrete(self):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     @patch('IM.connectors.OpenNebula.OpenNebulaCloudConnector.getONEVersion')
     def test_20_launch(self, getONEVersion, server_proxy):
         radl_data = """
@@ -139,7 +142,7 @@ def test_20_launch(self, getONEVersion, server_proxy):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     def test_30_updateVMInfo(self, server_proxy):
         radl_data = """
             network net ()
@@ -175,7 +178,7 @@ def test_30_updateVMInfo(self, server_proxy):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     def test_40_stop(self, server_proxy):
         auth = Authentication([{'id': 'one', 'type': 'OpenNebula', 'username': 'user',
                                 'password': 'pass', 'host': 'server.com:2633'}])
@@ -195,7 +198,7 @@ def test_40_stop(self, server_proxy):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     def test_50_start(self, server_proxy):
         auth = Authentication([{'id': 'one', 'type': 'OpenNebula', 'username': 'user',
                                 'password': 'pass', 'host': 'server.com:2633'}])
@@ -215,7 +218,7 @@ def test_50_start(self, server_proxy):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     @patch('IM.connectors.OpenNebula.OpenNebulaCloudConnector.checkResize')
     def test_55_alter(self, checkResize, server_proxy):
         radl_data = """
@@ -266,7 +269,7 @@ def test_55_alter(self, checkResize, server_proxy):
         self.assertNotIn("ERROR", self.log.getvalue(), msg="ERROR found in log: %s" % self.log.getvalue())
         self.clean_log()
 
-    @patch('xmlrpclib.ServerProxy')
+    @patch('IM.connectors.OpenNebula.ServerProxy')
     def test_60_finalize(self, server_proxy):
         auth = Authentication([{'id': 'one', 'type': 'OpenNebula', 'username': 'user',
                                 'password': 'pass', 'host': 'server.com:2633'}])
diff --git a/test/unit/connectors/OpenStack.py b/test/unit/connectors/OpenStack.py
index 6d7392e59..9514fb3c5 100755
--- a/test/unit/connectors/OpenStack.py
+++ b/test/unit/connectors/OpenStack.py
@@ -21,7 +21,10 @@
 import os
 import logging
 import logging.config
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 sys.path.append(".")
 sys.path.append("..")
diff --git a/test/unit/test_ansible.py b/test/unit/test_ansible.py
index 04695ee3c..c16125931 100755
--- a/test/unit/test_ansible.py
+++ b/test/unit/test_ansible.py
@@ -19,7 +19,10 @@
 import unittest
 import os
 from multiprocessing import Queue
-from StringIO import StringIO
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 import time
 
 from IM.ansible_utils.ansible_launcher import AnsibleThread
@@ -44,7 +47,7 @@ def test_ansible_thread(self):
         self.assertEqual(return_code, 0)
         self.assertIn("failed=0", output.getvalue())
         self.assertIn("changed=2", output.getvalue())
-        print output.getvalue()
+        print(output.getvalue())
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/test/unit/test_im_logic.py b/test/unit/test_im_logic.py
index 2d9f65361..f82b9a798 100755
--- a/test/unit/test_im_logic.py
+++ b/test/unit/test_im_logic.py
@@ -120,7 +120,7 @@ def test_inf_creation0(self):
         IM.DestroyInfrastructure(infId, auth0)
 
     def test_inf_creation1(self):
-        """Create infrastructure with empty RADL."""
+        """Create infrastructure with an incorrect RADL with 2 clouds."""
 
         radl = """"
             network publica (outbound = 'yes')
@@ -160,6 +160,55 @@ def test_inf_creation1(self):
                       " are asked to be deployed in different cloud providers",
                       str(ex.exception))
 
+    def test_inf_creation_addition_clouds(self):
+        """Add resources infrastructure with an incorrect RADL with 2 clouds."""
+
+        radl = """"
+            network publica (outbound = 'yes')
+            network privada ()
+
+            system front (
+            cpu.arch='x86_64' and
+            cpu.count>=1 and
+            memory.size>=512m and
+            net_interface.0.connection = 'publica' and
+            net_interface.1.connection = 'privada' and
+            disk.0.image.url = 'mock0://linux.for.ev.er' and
+            disk.0.os.credentials.username = 'ubuntu' and
+            disk.0.os.credentials.password = 'yoyoyo' and
+            disk.0.os.name = 'linux'
+            )
+
+            system wn (
+            cpu.arch='x86_64' and
+            cpu.count>=1 and
+            memory.size>=512m and
+            net_interface.0.connection = 'privada' and
+            disk.0.image.url = 'mock0://linux.for.ev.er' and
+            disk.0.os.credentials.username = 'ubuntu' and
+            disk.0.os.credentials.password = 'yoyoyo' and
+            disk.0.os.name = 'linux'
+            )
+
+            deploy front 1 cloud0
+            deploy wn 1
+        """
+
+        auth0 = self.getAuth([0], [], [("Dummy", 0), ("Dummy", 1)])
+        infId = IM.CreateInfrastructure(radl, auth0)
+        
+        radl = """
+            network privada
+            system wn
+            deploy wn 1 cloud1
+        """
+        
+        with self.assertRaises(Exception) as ex:
+            _ = IM.AddResource(infId, radl, auth0)
+        self.assertIn("Two deployments that have to be launched in the same cloud provider"
+                      " are asked to be deployed in different cloud providers",
+                      str(ex.exception))
+
     def test_inf_auth(self):
         """Try to access not owned Infs."""
 
@@ -191,7 +240,7 @@ def test_inf_addresources_without_credentials(self):
         with self.assertRaises(Exception) as ex:
             IM.AddResource(infId, str(radl), auth0)
 
-        self.assertIn("No username", ex.exception.message)
+        self.assertIn("No username", str(ex.exception))
 
         IM.DestroyInfrastructure(infId, auth0)
 
@@ -238,7 +287,7 @@ def test_inf_addresources1(self):
         """Deploy n independent virtual machines."""
 
         n = 20  # Machines to deploy
-        Config.MAX_SIMULTANEOUS_LAUNCHES = n / 2  # Test the pool
+        Config.MAX_SIMULTANEOUS_LAUNCHES = int(n / 2)  # Test the pool
         radl = RADL()
         radl.add(system("s0", [Feature("disk.0.image.url", "=", "mock0://linux.for.ev.er"),
                                Feature("disk.0.os.credentials.username", "=", "user"),