On 08/10/2012 05:31 PM, Harish Patil wrote:
> Hi
> I have both host and KVM/QEMU guest VM running linux.
>
> Questions:
> What are the constituents of the virsh dump?
> -  What all areas does it dumps?

By default, it dumps in the same format needed to migrate a VM from one
host to another.  As of 0.9.13 and new enough qemu (basically, a feature
in qemu.git but not released until the upcoming qemu 1.2), you can also
use 'virsh dump --memory-only' to force a dump to an ELF image instead.

> -  Is it same as taking guest VM's core dump via kexec/kdump?

If you use the --memory-only option, then it is very similar (although
the dump is performed without guest involvement).  If you want an actual
kexec/kdump from the guest, then you'll have to have the guest create
that; it may be worth requesting a qemu-ga guest agent command to
trigger a guest to dump itself.

> -  Does it include QEMU's info to debug qemu-level issues?

No, it is not a core dump of the qemu process itself.

--
Eric Blake   eblake@redhat.com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org