[Libguestfs] P2Vs seem to require a very robust Ethernet

[Greg Scott]

> There's something ugly going on with the network.  . . . 

And to close the loop on this issue for anyone else trying P2V migrations.  Turns out, there were two independent problems that interacted to make a big mess.  

Problem #1 - I promise never again to set up a 100mb NFS server with gb NFS clients.  Apparently, a fast NFS client quickly swamps the slow NFS server with read requests when trying to bulk-copy anything from that NFS server. Curiously, a fast NFS client can write to a slow NFS server just fine.  It's **reading** from a slow NFS server that messes it up.  Go figure.

Problem #2 - See Red Hat Bugzilla number 754331.  When my first RHEV host NFS client became hopelessly lost, I rebooted it and it refused to connect with the world after it came back up.  After spending 4 days of my life and countless hours of Red Hat support, it turned out that my RHEV host had an extra bogus bridge device named breth0 and that bogus bridge device messed up its communication with the world.  

After I fixed the bridge issue and we put a gb NIC in the NFS server, I was able to successfully - and quickly - import our P2V'd test VM into our RHEV environment.  

- Greg