I am running Microsoft Hyper-V Server 2008 R2 and have 2 Linux guests running. I have noticed that if I increase the number of processors that are available to the Linux guest networking doesn't seem to work when booted into the OS. It does look like it was able to get an IP address from DHCP, but if I try to renew with dhclient ethx then it timesout saying that a DHCP server hasn't responded.
However, once I set the number of processors to one then it works perfectly.
Legacy network adapter
Am I doing something wrong?