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RE: [Xen-users] Xen guests clock is exactly 2 hours before dom0 time

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Subject: RE: [Xen-users] Xen guests clock is exactly 2 hours before dom0 time
From: "Dustin Henning" <Dustin.Henning@xxxxxxxxxxx>
Date: Fri, 11 Jul 2008 16:03:52 -0400
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        I'm curious regarding this as well, only in a different way.  For
one, I did a little search, and what I found lead me to believe that setting
/proc/sys/xen/independent_wallclock to 1 in DomUs makes them ignore the xen
clock (where 0 is default and the xen clock is used).  That said, this
presumably only applies in a paravirtual environment.  However, assuming my
understanding of this feature is correct, it wouldn't exist in HVM domains
because there is no /proc/sys/xen (in Linux, much less in Windows).  That
said, I got my Windows machines to display the right time by using
rtc_timeoffset, but I had to make the system clock use UTC, and therefore I
have to change the offset for DST (rtc_timeoffset=-14400 for EDT and
rtc_timeoffset=-18000 for EST).  That is a pain and I would prefer to have a
separate virtual hardware clock for each HVM DomU instead of having them
bound to whatever time Xen says it is. Does such an option exist?  If it
does, would it use some token to keep track of the DomU time vs the Dom0
time at shutdown so it could match the time passed in real life since
shutdown at next startup (create in my case, using old python scripts), or
would it still use the rtc_timeoffset, leaving me in the same boat?

-----Original Message-----
From: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
[mailto:xen-users-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Ralf Hornik
Sent: Thursday, July 10, 2008 17:16
To: Xen Users
Subject: [Xen-users] Xen guests clock is exactly 2 hours before dom0 time

Hi list,

one and hopefully last strange thing I figured out ist the systime of  
my guests.

Dom0 uses ntp for time syncronisation. I set the time on my guests  
manually but after reboot any machine (Windows server, XP, Freebsd,  
even PV Machines like ubuntu) all run local time - 2 hours.

/proc/sys/xen/independent_wallclock is set to 0 so actually the time  
should be set by dom0...(?)

Any ideas, what this could be?

Best regards


alles bleibt anders...

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