vhostuser: connectivity lost if VPP is restarted on host

[egernst]

Description of problem

If you have two kata containers running with docker network provided by VPP (CNM plugin, for example) and you reset VPP on the host, connectivity between the containers is lost.

Expected result

I probably expect this to happen, given that VPP is the server for the vhost-user connection, and that VPP is stateless. The container continues to work, but without functional connectivity.

Taking a look at the FDIO Vhost User documents, it is conceivable that we could make the VM the server on the vhost-user connection. With this done, it is possible that connectivity could be recovered.

As far as I can tell, this would need to be done in an agent on the host or within the VPP CNM plugin , and is really out of the scope of Kata Containers itself.