Hi, I am facing problem in sync time within DomU with Dom0. After gone through mailing lists, I have set /proc/sys/xen/independent_wallclock to 0. But still DomU are not syncing their time :-S Machine using kernel-xen-2.6.19-1.2911.fc6 xen-3.0.3-3.fc6 xen-libs-3.0.3-3.fc6 Please advice to solve this weird problem, Thanks _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, 2007-02-20 at 21:07 +0500, Nadeem Shahbaz wrote:> Hi, > I am facing problem in sync time within DomU with Dom0. After gone > through mailing lists, I have set /proc/sys/xen/independent_wallclock > to 0. But still DomU are not syncing their time :-S Machine using > kernel-xen-2.6.19-1.2911.fc6 > xen-3.0.3-3.fc6 > xen-libs-3.0.3-3.fc6 > > Please advice to solve this weird problem, ThanksHave you also reported this to the fedora-xen lists? That is an interesting quirk, indeed. Best, --Tim> > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, 2007-02-20 at 21:07 +0500, Nadeem Shahbaz wrote: Sorry for the double bang, doh - I forgot to ask, how far are they drifting? Is each dom-u an equal distance away from dom-0 on the time line, or is this a random jitter for each guest? Thanks, and sorry again for double posting --Tim> Hi, > I am facing problem in sync time within DomU with Dom0. After gone > through mailing lists, I have set /proc/sys/xen/independent_wallclock > to 0. But still DomU are not syncing their time :-S Machine using > kernel-xen-2.6.19-1.2911.fc6 > xen-3.0.3-3.fc6 > xen-libs-3.0.3-3.fc6 > > Please advice to solve this weird problem, Thanks > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On 20 Feb 2007 at 21:07, Nadeem Shahbaz wrote:> Hi, > I am facing problem in sync time within DomU with Dom0. After gone > through mailing lists, I have set /proc/sys/xen/independent_wallclock > to 0. But still DomU are not syncing their time :-S Machine usingThen you missed my messages on how it actually did work. I think 0 is the default. So if the default is bad four you, try a change! Ulrich> kernel-xen-2.6.19-1.2911.fc6 > xen-3.0.3-3.fc6 > xen-libs-3.0.3-3.fc6 > > Please advice to solve this weird problem, Thanks > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Wed, 2007-02-21 at 09:31 +0100, Ulrich Windl wrote:> On 20 Feb 2007 at 21:07, Nadeem Shahbaz wrote: > > > Hi, > > I am facing problem in sync time within DomU with Dom0. After gone > > through mailing lists, I have set /proc/sys/xen/independent_wallclock > > to 0. But still DomU are not syncing their time :-S Machine using > > Then you missed my messages on how it actually did work. I think 0 is the default. > So if the default is bad four you, try a change!0 is the default, meaning ! independent wall clocks. I don''t see how altering this value to 1 can help solve his issue? While I do appreciate and employ your problem solving method frequently I don''t think it applies here... Unless of course the poster just gives up sets them independently and maintains an ntp time sync across the guests to dom-0. That means its still broken, just not annoying anymore. Not sure about the poster, but that would bug me relentlessly until I determined the issue. Best, --Tim> > Ulrich > > > kernel-xen-2.6.19-1.2911.fc6 > > xen-3.0.3-3.fc6 > > xen-libs-3.0.3-3.fc6 > > > > Please advice to solve this weird problem, Thanks > > > > _______________________________________________ > > Xen-users mailing list > > Xen-users@lists.xensource.com > > http://lists.xensource.com/xen-users > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Oops, Sent to Tim personally :-(, sending again On 2/21/07, Tim Post <tim.post@netkinetics.net> wrote:> > Have you also reported this to the fedora-xen lists? >:-( not yet but i am posting this issue there as well On 2/21/07, Tim Post <tim.post@netkinetics.net> wrote:> > Sorry for the double bang, doh - I forgot to ask, how far are they > drifting? Is each dom-u an equal distance away from dom-0 on the time > line, or is this a random jitter for each guest? >They gradually increased and this has increased to 9 secs now. There are 4 DomU and atm they are ahead of Dom0 by 7, 9, 8, 9 secs. On 2/21/07, Tim Post <tim.post@netkinetics.net> wrote:> On Wed, 2007-02-21 at 09:31 +0100, Ulrich Windl wrote: > > On 20 Feb 2007 at 21:07, Nadeem Shahbaz wrote: > > > > > Hi, > > > I am facing problem in sync time within DomU with Dom0. After gone > > > through mailing lists, I have set /proc/sys/xen/independent_wallclock > > > to 0. But still DomU are not syncing their time :-S Machine using > > > > Then you missed my messages on how it actually did work. I think 0 is the default. > > So if the default is bad four you, try a change! > > 0 is the default, meaning ! independent wall clocks. I don''t see how > altering this value to 1 can help solve his issue? While I do appreciate > and employ your problem solving method frequently I don''t think it > applies here... >According to the previous mail list, what I understand, if /proc/sys/xen/independent_wallclock is set to 0, all DomU will sync their time with Dom0. And most interesting thing is that we have another machine with same xen configuration and its DomU are sync with Dom0. We did try to set independent_wallclock to 1 and running ntp client at each DomU to sync time but it didnt help either as they drift ~500ms _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On 21 Feb 2007 at 17:11, Tim Post wrote:> On Wed, 2007-02-21 at 09:31 +0100, Ulrich Windl wrote: > > On 20 Feb 2007 at 21:07, Nadeem Shahbaz wrote: > > > > > Hi, > > > I am facing problem in sync time within DomU with Dom0. After gone > > > through mailing lists, I have set /proc/sys/xen/independent_wallclock > > > to 0. But still DomU are not syncing their time :-S Machine using > > > > Then you missed my messages on how it actually did work. I think 0 is the default. > > So if the default is bad four you, try a change! > > 0 is the default, meaning ! independent wall clocks. I don''t see how > altering this value to 1 can help solve his issue? While I do appreciate > and employ your problem solving method frequently I don''t think it > applies here...XEN (as of SLES10 x86_64) seemed to fail to sync the DomU clocks, so I started to sync them with NTP. This works, and I''m quite satisfied with it (even though our primary server has failed): # ntpq -p remote refid st t when poll reach delay offset jitter ============================================================================= LOCAL(0) LOCAL(0) 10 l 44 64 377 0.000 0.000 0.001 -rkdvmso5.dvm.kl 192.168.0.11 4 u 536 1024 377 0.153 6.311 0.149 -rksapas01.dvm.k 192.168.0.48 6 u 991 1024 377 0.001 -1.038 0.812 -rksapas02.dvm.k 192.168.0.44 7 u 865 1024 376 0.001 -5.087 0.809 -rksapas03.dvm.k 192.168.0.44 7 u 976 1024 377 0.209 -3.898 1.396 +rksapas04.dvm.k 192.168.0.48 6 u 682 1024 377 0.323 0.278 0.802 +rksapas05.dvm.k 192.168.0.48 6 u 667 1024 377 0.351 0.564 0.782 *rksapas06.dvm.k 192.168.0.63 5 u 544 1024 376 4.418 0.667 0.038 -rksapas07.dvm.k 192.168.0.48 6 u 897 1024 377 0.001 -0.751 0.829 -rksapas08.dvm.k 192.168.0.64 5 u 140 1024 376 0.317 3.123 0.810 -rksapas10.dvm.k 192.168.0.44 7 u 789 1024 376 0.001 -3.955 0.768 (Every server is a XEN para-virtual host)> > Unless of course the poster just gives up sets them independently and > maintains an ntp time sync across the guests to dom-0. > > That means its still broken, just not annoying anymore. Not sure about > the poster, but that would bug me relentlessly until I determined the > issue.Maybe some /proc/xen/clock_stats would be helpful to find out more on the XEN built-in clock synchronisation not working to everybody''s satisfaction. Personally I believe that independent clocks keep up the illusion that a virtual server is a real server. Regards, Ulrich _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On 22 Feb 2007 at 17:35, Nadeem Shahbaz wrote:> On 2/21/07, Ulrich Windl <ulrich.windl@rz.uni-regensburg.de> wrote: > > > > XEN (as of SLES10 x86_64) seemed to fail to sync the DomU clocks, so I started to > > sync them with NTP. This works, and I''m quite satisfied with it (even though our > > primary server has failed): > > > > Yes, infact we tried it too but clock was always drifted with >500ms :-(Unfortunately, neither XEN, nor NTP is a software to repair broken hardware. You could use another time sync software. Regards, Ulrich _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Okay, this problem is solved. I didn''t know that /proc/sys/xen/independent_wallclock does exist in DomU and it did effect time sync with Dom0. As /proc/sys/xen/independent_wallclock was forced set to 1 in DomU and 0 in Dom0 somehow. Now setting this to 0 solved the problem and now DomU are in sync with Dom0. And I really appreciate for helping and thanks :-) And sorry Ulrich, I only replied you unintentionally :-) _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users