Autor: Matt Rubright Data: A: exim-users Assumpte: Re: [exim] System time correction during or after Exim startup
affects queue time
Would this happen to be running under Xen HVM? When starting a new
guest under Xen HVM, the time is apparently initialized from the Xen
hypervisor itself, not from the good time kept in Dom0. Xen's time is
not corrected by NTP. When the physical host has been running for a
very long time, drift would be significant. I have observed this issue
on Xen hosts I manage myself. I've never taken the time to discuss this
upstream, or confirm the issue still exists with current Xen versions.
The thing is, this has caused me problems as it is causing you, and you
are a paying Amazon customer. Why don't you try to get them to
contribute a fix?
Meanwhile, you can set up ntpdate to run and hard-step the clock right
before NTP starts and certainly before any mail-related, database or
any important record-keeping things start up.
Thanks for these suggestions. These are certainly running under Xen, and
this is likely the nature of the problem. I believe I have a workaround
ready for the next time I get an outage on these servers. I'll have to
consider whether or not it's worth punching Amazon over.
