From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Novotny Subject: Re: [PATCH] Fix restore handling checks Date: Tue, 22 Jun 2010 07:43:40 +0200 Message-ID: <4C204D8C.3020303@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: "'xen-devel@lists.xensource.com'" List-Id: xen-devel@lists.xenproject.org On 06/21/2010 08:04 PM, Keir Fraser wrote: > On 21/06/2010 17:30, "Michal Novotny" wrote: > > >> Hi, >> this is the patch to fix restore handling to implement some more checks >> to support more checks than for UUID and name duplicity. This patch >> basically disallows the migration/restore of IDE drives with the >> read-only flag since this is not supported according to the ATAPI/IDE >> specifications so we should disallow this for both domain creation and >> domain migration/restore. >> > What about CD-ROMs? This would break my test domain config, for example. > > Right, there's the exception for CD-ROMs according to the spec. I should implement this as well but read-only IDE disk devices are not supported according to the IDE specs. >> This patch implements it for both create and >> restore/migrate functionality. >> >> Also, the check whether the host machine does have enough memory >> available for the guest has been implemented which can be the real issue >> when you try to migrate a guest from one machine to another that is not >> having enough memory for this guest. The guest memory gets transferred >> but it fails to run so it's not running on either of those machines >> (i.e. domain is not on the destination nor source host machine). >> > Failed restore should get reported back to the host that is saving the guest > state, and cause that machine to resume execution of the original VM. Does > that not work for you? > > Possibly checking up front for available memory on the target is a good > idea, but it shouldn't be *essential* if the error handling is up to par. > > -- Keir > It was not working but I'm still coping with some issues that are save/restore related so maybe this is the reason why I was unable to see this behaviour. Michal > >> I did try it with restore functionality now since I've been able to make >> it working for save once so I'm currently using one save image for the >> testing but unfortunately I'm having many issues with the common >> migration and save functionality since I've been able to make it working >> once to save it correctly. Fortunately the restores for this one >> particular save image is working fine. I was also thinking about 2 >> concurrent migrations to the guest and/or save with the concurrent >> migration and it should be the issue (although it's not been tested >> because of reasons described above) since the domain gets created and >> it's available in the XendDomain list (i.e. xc.domain_getinfo() list) so >> it shouldn't be an issue here. >> >> Michal >> >> Signed-off-by: Michal Novotny >> > > -- Michal Novotny, RHCE Virtualization Team (xen userspace), Red Hat