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On 01-11-16 15:22:57, Carlton, Paul (Cloud Services) wrote:
> Lee
> 
> That change is in my test version or was till I reverted it with https://review.openstack.org/#/c/391418,
> 
> If you live migrate with the change you mentioned the instance goes to error when you try to hard reboot

Hey Paul,

I can't see a bug referenced by the revert above, have you looked into
why this is happening and if a full revert is really required? It might
be easier to fix this corner case, leaving the new method of fetching
the domain XML in post_live_migration_at_destination and thus working
around your issue.

Lee

> From: Lee Yarwood <lyarwood at redhat.com>
> Sent: 01 November 2016 14:58:58
> To: OpenStack Development Mailing List (not for usage questions)
> Subject: Re: [openstack-dev] [nova] [cinder] Issue with live migration of instances with encrypted volumes
> 
> On 01-11-16 12:02:55, Carlton, Paul (Cloud Services) wrote:
> > Daniel
> >
> > Yes, thanks, but the thing is this does not occur with regular volumes!
> > The process seems to be you need to connect the volume then the encryptor.
> > In pre migration at the destination I connect the volume and then setup the encryptor and that works fine, but in post migration
> > at destination it rebuilds the instance xml and defines the vm which calls _get_guest_storage_config which does another call to
> > connect_volume.  This seems redundant to me, because it is already connected,
> > but it works for normal volumes and if I bypass it for encrypted volumes
> > it just fails with the same error when the same function is
> > called as part of a subsequent hard reboot.
> 
> Try rebasing on the following change that reworked
> post_live_migration_at_destination to fetch the domain XML from libvirt
> instead of asking Nova to rebuild it :
> 
> libvirt: fix serial console not correctly defined after live-migration
> https://review.openstack.org/#/c/356335/
> 
> I think you've highlighted that this caused issues with hard rebooting
> elsewhere right?
> 
> Lee
> 
> > From: Daniel P. Berrange <berrange at redhat.com>
> > Sent: 01 November 2016 11:29:51
> > To: OpenStack Development Mailing List (not for usage questions)
> > Subject: Re: [openstack-dev] [nova] [cinder] Issue with live migration of instances with encrypted volumes
> >
> > On Tue, Nov 01, 2016 at 11:22:25AM +0000, Carlton, Paul (Cloud Services) wrote:
> > > I'm working on a bug https://bugs.launchpad.net/nova/+bug/1633033 with the live migration of
> > >
> > > instances with encrypted volumes. I've submitted a work in progress version of a patch
> > >
> > > https://review.openstack.org/#/c/389608 but I can't overcome an issue with an iscsi command
> > >
> > > failure that only occurs for encrypted volumes during the post migration processing, see
> > >
> > > http://paste.openstack.org/show/587535/
> > >
> > >
> > > Does anyone have any thoughts on how to proceed with this issue?
> >
> > No particular ideas, but I wanted to point out that the scsi_id command
> > shown in that stack trace has a device path that points to the raw
> > iSCSI LUN, not to the dm-crypt overlay. So it looks like you're hitting
> > a failure before you get the encryption part, so encryption might be
> > unrelated.

-- 
Lee Yarwood
Senior Software Engineer
Red Hat

PGP : A5D1 9385 88CB 7E5F BE64  6618 BCA6 6E33 F672 2D76