[ClusterLabs] XenServer guest and host watchdog

Valentin Vidic Valentin.Vidic at CARNet.hr
Fri Sep 8 16:20:58 EDT 2017

On Fri, Sep 08, 2017 at 12:57:12PM +0000, Mark Syms wrote:
> As we discussed regarding the handling of watchdog in XenServer, both
> guest and host, I've had a discussion with our subject matter expert
> (Andrew, cc'd) on this topic. The guest watchdogs are handled by a
> hardware timer in the hypervisor but if the timers themselves are not
> serviced within 5 seconds the host watchdog will fire and pull the
> host down.

I presume the host watchdog is the NMI watchdog described in the
Xen Hypervisor Command Line Options?

watchdog = force | <boolean> (Default: false)
Run an NMI watchdog on each processor. If a processor is stuck for
longer than the watchdog_timeout, a panic occurs. When force is
specified, in addition to running an NMI watchdog on each processor,
unknown NMIs will still be processed.

watchdog_timeout = <integer> (Default: 5)
Set the NMI watchdog timeout in seconds. Specifying 0 will turn off the


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