[CentOS-virt] Xen domU default gateway missing/ARP table full

[Ed Heron]

  I was slightly confused about this thread until I realized you were using 
static IP config on your VM's...

  Why do people do that?  I have an extra step of picking up the HW address 
(or setting the HW address when creating the VM) and putting it into my dhcp 
configuration, but then I have all of my hosts in a single file and I can 
change the network configuration of my whole network in a single place.

  I realize that my DHCP server becomes a single point of failure, but with 
a reasonably long retrain time the DHCP server going down won't effect any 
workstations for as much as several hours (as long as nothing reboots). 
Also, there are ways of having fault tolerance with DHCP, the easiest would 
be to have a non running VM with a copy of the data.