Hey folks, I am trying to live migrate a guest from a Xeon machine to core i 7 machine and reverse, and my problem is Xeon machine get restarted randomly. The restarting happens both when I migrate from it or to it. The weird part is it happens sometimes, like 40 percent of time the migration works perfectly fine and sometimes Xeon machine gets restarted, I first thought problem is with the memory size of guests but reducing it didn''t resolve the issue. The xeon machine has 12 GB of memory and core i 7 has 8, my guest has 2 GB of memory and I only have one guest. Let me know if you have any thoughts, Regards Reza _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On Mon, 2013-11-18 at 21:02 -0500, reza azimi wrote:> Hey folks, > > > I am trying to live migrate a guest from a Xeon machine to core i 7 > machine and reverse, and my problem is Xeon machine get restarted > randomly.Did you reduce the cpuid exposed to the guest to the lowest common denominator here? I''ve no ideal how similar those two processors are but I suppose they aren''t identical. Ian.
Let me first fix one thing, the title should be fixed to "DOM 0 get restarted during live migration", The xeon machine get restarted during the migration both when it receiving a guest or sending a guest. Second thanks Ian for the reply, sorry I''m very new to xen what do you mean by "Did you reduce the cpuid exposed to the guest to the lowest common denominator here", in my config file I''ve putted vcpus = 2, xeon machine has 8 cores and intel machine has 4 cores so I thought 2 out of 8 or 4 can not cause a problem. should mention something like this to explicitlymention which cpus to use? for ex: cpus = ["2", "3"] Is there any log file that I can see the time pre copy and stop and copy start/finish. Maybe I can find some relation there? Also I''ve heard there are some settings for migration like the memory threshold value that remain before starting the "stop and copy" and number of iteration that it try in "pre copy" and etc. how can see/change these settings? Regards Reza On Tue, Nov 19, 2013 at 7:31 AM, Ian Campbell <Ian.Campbell@citrix.com>wrote:> On Mon, 2013-11-18 at 21:02 -0500, reza azimi wrote: > > Hey folks, > > > > > > I am trying to live migrate a guest from a Xeon machine to core i 7 > > machine and reverse, and my problem is Xeon machine get restarted > > randomly. > > Did you reduce the cpuid exposed to the guest to the lowest common > denominator here? I''ve no ideal how similar those two processors are but > I suppose they aren''t identical. > > Ian. > > >_______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On Wed, 2013-11-20 at 12:40 -0500, reza azimi wrote:> Let me first fix one thing, the title should be fixed to "DOM 0 get > restarted during live migration", The xeon machine get restarted > during the migration both when it receiving a guest or sending a > guest.Please can you collect a console log. Preferable via a serial console http://wiki.xen.org/wiki/Xen_Serial_Console> Second thanks Ian for the reply, sorry I''m very new to xen what do you > mean by "Did you reduce the cpuid exposed to the guest to the lowest > common > denominator here", in my config file I''ve putted vcpus = 2, xeon > machine has 8 cores and intel machine has 4 cores so I thought 2 out > of 8 or 4 can not cause a problem. should mention something like this > to explicitly mention which cpus to use? for ex: cpus = ["2", "3"] > Is there any log file that I can see the time pre copy and stop and > copy start/finish. Maybe I can find some relation there?I didn''t mean the numbers of CPUs but rather the CPU features, i.e. the CPUID (presence of SSE, SSE2 all that sort of thing, which differs across different families of processor etc). However if this is crashing the host then this is not really relevant any more> Also I''ve heard there are some settings for migration like the memory > threshold value that remain before starting the "stop and copy" and > number of iteration that it try in "pre copy" and etc. how can > see/change these settings?I doubt that is related to your crash. Ian.
Thanks Ian, I will try to do that, unfortunately I couldnt find time today to doing that. Meanwhile I found this page: https://wiki.debian.org/Xen#dom0_automatic_reboots which recommend to add the below to the grub when DOM 0 get restarted: GRUB_CMDLINE_XEN="noreboot" I''ve done that and the result is the xeon machine doesnt get restarted but instead it freeze and I have to power it off and on. when there is nothing running on the guests the restarting issue doesnt happen but when I run something and then try to migrate the guest it happens. I though to share it maybe it helps to find what is the problem. Regards Reza On Wed, Nov 20, 2013 at 12:44 PM, Ian Campbell <Ian.Campbell@citrix.com>wrote:> On Wed, 2013-11-20 at 12:40 -0500, reza azimi wrote: > > Let me first fix one thing, the title should be fixed to "DOM 0 get > > restarted during live migration", The xeon machine get restarted > > during the migration both when it receiving a guest or sending a > > guest. > > Please can you collect a console log. Preferable via a serial console > http://wiki.xen.org/wiki/Xen_Serial_Console > > > Second thanks Ian for the reply, sorry I''m very new to xen what do you > > mean by "Did you reduce the cpuid exposed to the guest to the lowest > > common > > denominator here", in my config file I''ve putted vcpus = 2, xeon > > machine has 8 cores and intel machine has 4 cores so I thought 2 out > > of 8 or 4 can not cause a problem. should mention something like this > > to explicitly mention which cpus to use? for ex: cpus = ["2", "3"] > > Is there any log file that I can see the time pre copy and stop and > > copy start/finish. Maybe I can find some relation there? > > I didn''t mean the numbers of CPUs but rather the CPU features, i.e. the > CPUID (presence of SSE, SSE2 all that sort of thing, which differs > across different families of processor etc). > > However if this is crashing the host then this is not really relevant > any more > > > Also I''ve heard there are some settings for migration like the memory > > threshold value that remain before starting the "stop and copy" and > > number of iteration that it try in "pre copy" and etc. how can > > see/change these settings? > > I doubt that is related to your crash. > > Ian. > > >_______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
On Thu, 2013-11-21 at 01:27 -0500, reza azimi wrote:> Thanks Ian, I will try to do that, unfortunately I couldnt find time > today to doing that. > Meanwhile I found this page: > https://wiki.debian.org/Xen#dom0_automatic_reboots > > which recommend to add the below to the grub when DOM 0 get restarted: > GRUB_CMDLINE_XEN="noreboot" > I''ve done that and the result is the xeon machine doesnt get restarted > but instead it freeze and I have to power it off and on.Well, yes, that''s what noreboot means... Did this allow you to see any logs on the screen? If you cannot do a serial console then a photograph of the VGA would be a fallback, but make sure you''ve turned up the logging level etc.> when there is nothing running on the guests the restarting issue > doesnt happen but when I run something and then try to migrate the > guest it happens. > I though to share it maybe it helps to find what is the problem.As I say we need logs to make progress here, when you get a chance. Ian.