Vagrant + NFS + MPI

A simple tutorial for clustering using Vagrant with an application on NFS and MPICH

Vagrantfile is well documented to better understand how it works!

Table of Contents

• Vagrant + NFS + MPI
  • What is Vagrant?
  • What is NFS?
  • What is MPI and MPICH?
  • Installation
    • Install Vagrant
      • Ubuntu-based OS
      • Windows and Other OSs
    • Install VirtualBox
      • Ubuntu-based OS
      • Windows and Other OSs
  • Run and Connect to VMs
  • Test Socket Connection
  • MPI Test on machines

What is Vagrant?

Vagrant is a tool for building and managing virtual machine environments in a single workflow. With an easy-to-use workflow and focus on automation, Vagrant lowers development environment setup time, increases production parity, and makes the "works on my machine" excuse a relic of the past.

What is NFS?

Network File System (NFS) is a distributed file system protocol, allowing a user on a client computer to access files over a computer network much like local storage is accessed.

What is MPI and MPICH?

Message Passing Interface (MPI) is a standardized and portable message-passing standard designed to function on parallel computing architectures.

MPICH is a high-performance and widely portable implementation of the Message Passing Interface (MPI)

Installation

The porocess of installation on your system (host) is simple.

Install Vagrant

After installation, remember that you can change the default path of Vagrant by setting VAGRANT_HOME to /path/to/your/directory in enviroment variables.

Ubuntu-based OS

curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt-get update && sudo apt-get install vagrant

Windows and Other OSs

Just follow the instrution on Vagrant Installation Page.

Install VirtualBox

Change the default path in menu File -> Preferences....

Ubuntu-based OS

sudo apt install virtualbox

Windows and Other OSs

Download and install from this link

Run and Connect to VMs

You can easily have a cluster with 3 nodes by running the following command.

git clone https://github.com/vahidmohsseni/vagrant-nfs-mpi
cd vagrant-nfs-mpi
vagrant up

To ssh and Connect to VM

vagrant ssh [name of the VM]
vagrant ssh server
vagrant ssh client2

To stop VMs

vagrant halt [name of specific VM]

To delete VMs

vagrant destory [name of specific VM]

Test Socket Connection

To make sure that the connection between clients and server nodes (VMs) is established and works properly, two python programs is written. The program is simple. Note that you should always run server FIRST. Moreover, every changes in socket_test directory directly affects the codes in VM after the VMs are up.

In server-side, it opens a socket binds and listens to port 9000 on server. Following instructions lets you to activate and run the program on the server. The program is multi-threaded which means it can handle multiple clients' connection simultaneously. To stop the server from terminal just use ctrl+c.

vagrant ssh server
python3 server.py

In client-side, it tries to establish a connection to server which is available in the address "192.168.10.2:9000". Following instruction helps to run this program.

vagrant ssh client2
python3 client.py

MPI Test on machines

The configuration in Vagrantfile commands to the installation of the MPICH on the VMs. After installation, you can have the MPI codes in shared directory (which is already shared by NFS). Note that clients should mount this directory in their local machines. The name of the direcotry should be same for all VMs. The MPI codes can be easily run through the machines only from server machine. Server should ssh to all Clients before executing MPI codes, otherwise there will be an error indicating Host key verification failed.

On server VM:

cd /mnt/mirror/mpi_codes
mpicc -o sample_mpi sample_mpi.c
mpirun -n 3 -f host_file ./sample_mpi

Output:

Hello World, My rank is 1 and size is 3 processors
Hello World, My rank is 0 and size is 3 processors
Hello World, My rank is 2 and size is 3 processors

On server VM:

mpicc -o mpi_example mpi_example.c
mpiexec -n 6 -f host_file ./mpi_example

Output:

Hello world from processor client1, rank 2 out of 6 processors
Hello world from processor client1, rank 5 out of 6 processors
Hello world from processor server, rank 0 out of 6 processors
Hello world from processor server, rank 3 out of 6 processors
Hello world from processor client2, rank 4 out of 6 processors
Hello world from processor client2, rank 1 out of 6 processors