XenServer 6.5(SP1) - HVM 're0: watchdog timeout' errors...

[Karl Pielorz]

Hi,

We have a bunch of FreeBSD 10.1 hosts we run the NIC's as HVM (this avoids 
a known networking issue with XenServer and PV networks under FreeBSD to do 
with routing packets for other Xen DomU).

This seems to work OK - but recently we've had a whole bunch of:

  Sep  7 12:41:08 host1 kernel: re0: watchdog timeout
...
  Sep  7 12:42:03 host1 kernel: re1: watchdog timeout


This seems to 'break' networking for the guest. I've tried doing 'ifconfig 
re0 down / ifconfig re0 up' - this doesn't appear to fix things - but 
rebooting the DomU guest does (when it comes back, networking is restored).

Searching around with Google turns up some similar issues with NetBSD along 
with the comment that the QEMU Realtek card doesn't have watchdog emulation 
- so it should be disabled in the driver.

How applicable to FreeBSD that is, I don't know.

This seems to happen when the VM's are migrated (e.g. Xen Storage Motion) 
from one SR to another - or migrated, full stop (i.e. from one XenServer to 
another - but using shared storage).

Anyone know if that same "there is no re watchdog" issue is a possible 
cause? - Or any suggestions for fixes?

-Karl