diff --git a/repos/system_upgrade/common/actors/ipuworkflowconfig/libraries/ipuworkflowconfig.py b/repos/system_upgrade/common/actors/ipuworkflowconfig/libraries/ipuworkflowconfig.py
index 73197e0b39..7abb2b4227 100644
--- a/repos/system_upgrade/common/actors/ipuworkflowconfig/libraries/ipuworkflowconfig.py
+++ b/repos/system_upgrade/common/actors/ipuworkflowconfig/libraries/ipuworkflowconfig.py
@@ -51,8 +51,12 @@ def get_os_release(path):
     try:
         with open(path) as f:
             data = dict(l.strip().split('=', 1) for l in f.readlines() if '=' in l)
+            release_id = data.get('ID', '').strip('"')
+            version_id = data.get('VERSION_ID', '').strip('"')
+            if release_id == 'centos' and '.' not in version_id:
+                os_version = "{}.999".format(version_id)
             return OSRelease(
-                release_id=data.get('ID', '').strip('"'),
+                release_id=release_id,
                 name=data.get('NAME', '').strip('"'),
                 pretty_name=data.get('PRETTY_NAME', '').strip('"'),
                 version=data.get('VERSION', '').strip('"'),
diff --git a/repos/system_upgrade/common/libraries/config/version.py b/repos/system_upgrade/common/libraries/config/version.py
index 95f0d23170..5eb80c9c54 100644
--- a/repos/system_upgrade/common/libraries/config/version.py
+++ b/repos/system_upgrade/common/libraries/config/version.py
@@ -16,7 +16,7 @@
 _SUPPORTED_VERSIONS = {
     # Note: 'rhel-alt' is detected when on 'rhel' with kernel 4.x
     '7': {'rhel': ['7.9'], 'rhel-alt': [], 'rhel-saphana': ['7.9'], 'centos': ['7.9'], 'eurolinux': ['7.9'], 'ol': ['7.9'], 'scientific': ['7.9']},
-    '8': {'rhel': ['8.5', '8.6', '8.8', '8.9', '8.10'], 'rhel-saphana': ['8.6', '8.8', '8.9', '8.10'], 'centos': ['8.5'], 'almalinux': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'eurolinux': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'ol': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'rocky': ['8.6', '8.7', '8.8', '8.9', '8.10']},
+    '8': {'rhel': ['8.5', '8.6', '8.8', '8.9', '8.10'], 'rhel-saphana': ['8.6', '8.8', '8.9', '8.10'], 'centos': ['8.5', '8.999'], 'almalinux': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'eurolinux': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'ol': ['8.6', '8.7', '8.8', '8.9', '8.10'], 'rocky': ['8.6', '8.7', '8.8', '8.9', '8.10']},
 }
 
 
diff --git a/repos/system_upgrade/common/libraries/module.py b/repos/system_upgrade/common/libraries/module.py
index abde69e703..7d4e8aa43b 100644
--- a/repos/system_upgrade/common/libraries/module.py
+++ b/repos/system_upgrade/common/libraries/module.py
@@ -1,4 +1,3 @@
-import os
 import warnings
 
 from leapp.libraries.common.config.version import get_source_major_version
@@ -23,14 +22,20 @@ def _create_or_get_dnf_base(base=None):
         # have repositories only for the exact system version (including the minor number). In a case when
         # /etc/yum/vars/releasever is present, read its contents so that we can access repositores on such systems.
         conf = dnf.conf.Conf()
-        pkg_manager = 'yum' if get_source_major_version() == '7' else 'dnf'
-        releasever_path = '/etc/{0}/vars/releasever'.format(pkg_manager)
-        if os.path.exists(releasever_path):
-            with open(releasever_path) as releasever_file:
-                releasever = releasever_file.read().strip()
-                conf.substitutions['releasever'] = releasever
-        else:
-            conf.substitutions['releasever'] = get_source_major_version()
+
+        # preload releasever from what we know, this will be our fallback
+        conf.substitutions['releasever'] = get_source_major_version()
+
+        # dnf on EL7 doesn't load vars from /etc/yum, so we need to help it a bit
+        if get_source_major_version() == '7':
+            try:
+                with open('/etc/yum/vars/releasever') as releasever_file:
+                    conf.substitutions['releasever'] = releasever_file.read().strip()
+            except IOError:
+                pass
+
+        # load all substitutions from etc
+        conf.substitutions.update_from_etc('/')
 
         base = dnf.Base(conf=conf)
         base.init_plugins()