'Live' Migrate messes up NTP on FreeBSD domU - any suggestions?

[Karl Pielorz]

Hi,

We run a number of 10.x boxes under XenServer 6.5. On those boxes we run 
NTP  as a client with a few local time servers on the network to keep the 
time in sync on that VM.

There's a number of big threads on the Citrix forums about whether you 
should, or shouldn't run NTP in domU's - but the consensus seems to be you 
need to in order to keep the domU's clock accurately in sync.

This works fine.

However if we run a live migrate (to another XenServer node) or Xen Storage 
Motion migration - the domU's ntp gets messed up. The time on the domU is 
generally "ok" - but ntpq gives output like:

"
ntpq> pe
     remote        refid      st t when poll reach   delay   offset jitter
===========================================================================
 ntp0      193.67.79.202    2 u  931 1024  377    0.232  -4977.5 4207.29
 ntp1       66.228.38.73    3 u  890 1024  377    0.267  -4988.5 4616.94
 ntp2      64.246.132.14    2 u  990 1024  377    0.324  -4978.0 4207.98
"

It *never* recovers from this (you have to log into the box, and restart 
ntpd).

I realise this may be more a 'ntpd' than Xen question - but does anyone 
have any suggestions for avoiding this happening? - i.e. Some option for 
ntp.conf or something?

Thanks,

-Karl