How to make two VMs communicate with each other? I have to split a task between two VMs, so I think MPI has to be used, If so are there any useful resources that I can use to get started? Any help would be appreciated.
P.S : I have instaled devstack juno
Your question is not really clear.
Openstack is just a virtualization technology. There's almost no difference between having two hardware servers and two VMs. E.g. normally if two servers belong to the same network segment they will have access to each other's open ports. Openstack works just in the same way - if you assign the same network to VMs then this will also work.
However if you wish to install two VMs that will consume from a list of tasks and do them in parallel I would recommend you to read about Enterprise Integration Patterns (e.g. here). Technically this is implemented by using one or several messaging middleware servers such as ActiveMQ or ZeroMQ.
