Hi,
I tried to do live migration from machine A to B. After the migration, machine A
still had the record of the VM, though the VM was not running any more. Also, if
I shut down the VM on machine B, its record on B would be gone --- I could not
see it using "xm list" anymore. However, I can still start the VM on
machine A using "xm start".
Looks like the migration just move the live version of the VM, while its record
still remains at the original machine. Is this the expected behavior?
Many thanks!
Doug
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Xen-users@lists.xensource.com
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It is the expected behaviour. It''s your responsibility to ensure that
the
domain isn''t started on more than one host at a time (this may be
enforced
by your shared storage solution).
-----Original Message-----
From: xen-users-bounces@lists.xensource.com
[mailto:xen-users-bounces@lists.xensource.com] On Behalf Of wei sun
Sent: May 16, 2008 5:10 PM
To: xen-users@lists.xensource.com
Subject: [Xen-users] Live migration not permanent?
Hi,
I tried to do live migration from machine A to B. After the migration,
machine A still had the record of the VM, though the VM was not running any
more. Also, if I shut down the VM on machine B, its record on B would be
gone --- I could not see it using "xm list" anymore. However, I can
still
start the VM on machine A using "xm start".
Looks like the migration just move the live version of the VM, while its
record still remains at the original machine. Is this the expected behavior?
Many thanks!
Doug
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
On Fri, May 16, 2008 at 6:38 PM, [STD]Ein <ein@anti-logic.com> wrote:> It is the expected behaviour. It''s your responsibility to ensure that the > domain isn''t started on more than one host at a time (this may be enforced > by your shared storage solution).Yep. The only thing live migration does is move the running domU from its current memory location on Host A, to a new memory location in Host B. It does not move any config files, and you MUST use shared storage to have a working domU on Host B after migration. You CAN migrate a domain that has storage local to Host A but not Host B, however, what happens is that on Host B, you get a running guest that can not access its filesystem, and much hilarity ensues when you try to do anything that involves accessing the filesystem. So, the requirements are: Host A --| ----- Shared Storage (I use Fiberchannel storage for this) Host B --| And, if you want to permenantly move the domU from host A to host B, you need to move the domU config file from hostA to hostB as well. Also, you could have Host A be a mirror of Host B (failover scenario) so if Host A bites the dust, you can run the domU to your heart''s content on Host B, since B has the config file too... YMMV, of course... _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Jeff Lane wrote:> On Fri, May 16, 2008 at 6:38 PM, [STD]Ein <ein@anti-logic.com> wrote: > >> It is the expected behaviour. It''s your responsibility to ensure that the >> domain isn''t started on more than one host at a time (this may be enforced >> by your shared storage solution). >> > > Yep. The only thing live migration does is move the running domU from > its current memory location on Host A, to a new memory location in > Host B. It does not move any config files, and you MUST use shared > storage to have a working domU on Host B after migration. You CAN > migrate a domain that has storage local to Host A but not Host B, > however, what happens is that on Host B, you get a running guest that > can not access its filesystem, and much hilarity ensues when you try > to do anything that involves accessing the filesystem. > > So, the requirements are: > > Host A --| > ----- Shared Storage (I use Fiberchannel storage for this) > Host B --| > > And, if you want to permenantly move the domU from host A to host B, > you need to move the domU config file from hostA to hostB as well. > > Also, you could have Host A be a mirror of Host B (failover scenario) > so if Host A bites the dust, you can run the domU to your heart''s > content on Host B, since B has the config file too... > > YMMV, of course... > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users > >So, how does one move a domU from one physical server to another physical server if there''s no shared storage in between? -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Tomasz Chmielewski wrote:> Rudi Ahlers schrieb: > > (...) > >>> And, if you want to permenantly move the domU from host A to host B, >>> you need to move the domU config file from hostA to hostB as well. >>> >>> Also, you could have Host A be a mirror of Host B (failover scenario) >>> so if Host A bites the dust, you can run the domU to your heart''s >>> content on Host B, since B has the config file too... >>> >>> YMMV, of course... > > >> So, how does one move a domU from one physical server to another >> physical server if there''s no shared storage in between? > > Live? It won''t work. Unless the guest does not base on any kind of > storage (i.e., everything was started in a hugish initrd). > > If offline, just copy storage, config... > >Oh, ok. I''ve new to XEN, and never done this before :) -- Kind Regards Rudi Ahlers CEO, SoftDux Web: http://www.SoftDux.com Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stuff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Rudi Ahlers schrieb: (...)>> And, if you want to permenantly move the domU from host A to host B, >> you need to move the domU config file from hostA to hostB as well. >> >> Also, you could have Host A be a mirror of Host B (failover scenario) >> so if Host A bites the dust, you can run the domU to your heart''s >> content on Host B, since B has the config file too... >> >> YMMV, of course...> So, how does one move a domU from one physical server to another > physical server if there''s no shared storage in between?Live? It won''t work. Unless the guest does not base on any kind of storage (i.e., everything was started in a hugish initrd). If offline, just copy storage, config... -- Tomasz Chmielewski http://wpkg.org _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Rudi Ahlers schreef:> So, how does one move a domU from one physical server to another > physical server if there''s no shared storage in between?Pause the machine, copy the image over. And unpause it on the otherside? Stefan _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Rudi Ahlers wrote:> So, how does one move a domU from one physical server to another > physical server if there''s no shared storage in between? >Shut down or save the domU; copy the config and vbd files to the other server; start or restore the domU. Takes a while if the disks are large :-( jch _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Mon, May 19, 2008 at 10:16 AM, Rudi Ahlers <Rudi@softdux.com> wrote:>>> So, how does one move a domU from one physical server to another physical >>> server if there''s no shared storage in between? >> >> Live? It won''t work. Unless the guest does not base on any kind of storage >> (i.e., everything was started in a hugish initrd). >> >> If offline, just copy storage, config...Yeah... I usually just scp the filesystem image from Host A to Host B, copy the config file likewise, and start the guest on Host B. Migration in Xen is a bit different than migration in VMWare... Another thing I''ve tried to varying success is to create a guest, the make a tarball of the guest and it''s config, and save that tarball on a storage server so I can deploy that same guest to multiple machines. That''s just something I do to ease testing... and it doesn''t always work... but simply copying the guest filesystem from one machine to another along with its config file works just fine. Cheers Jeff _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Jeff Lane wrote:> On Fri, May 16, 2008 at 6:38 PM, [STD]Ein <ein@anti-logic.com> wrote: > > It is the expected behaviour. It''s your responsibility to ensure that the > > domain isn''t started on more than one host at a time (this may be enforced > > by your shared storage solution). > > Yep. The only thing live migration does is move the running domU from > its current memory location on Host A, to a new memory location in > Host B. It does not move any config files, and you MUST use shared > storage to have a working domU on Host B after migration. You CAN > migrate a domain that has storage local to Host A but not Host B, > however, what happens is that on Host B, you get a running guest that > can not access its filesystem, and much hilarity ensues when you try > to do anything that involves accessing the filesystem. > > So, the requirements are: > > Host A --| > ----- Shared Storage (I use Fiberchannel storage for this) > Host B --| > > And, if you want to permenantly move the domU from host A to host B, > you need to move the domU config file from hostA to hostB as well. > > Also, you could have Host A be a mirror of Host B (failover scenario) > so if Host A bites the dust, you can run the domU to your heart''s > content on Host B, since B has the config file too... > > YMMV, of course...Now I believe if you add your domU to the xenstore with ''xm new <config>'' and work completely out of the xenstore then after migration the domU in the xenstore will be in Host B and not Host A so there should be no chance of starting a duplicate unless you do a ''xm create <config>''. -Ross ______________________________________________________________________ This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail, and any attachments thereto, is strictly prohibited. If you have received this e-mail in error, please immediately notify the sender and permanently delete the original and any copy or printout thereof. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
John Haxby <john.haxby@oracle.com> writes:> Rudi Ahlers wrote: >> So, how does one move a domU from one physical server to another >> physical server if there''s no shared storage in between? >> > > Shut down or save the domU; copy the config and vbd files to the other > server; start or restore the domU. > > Takes a while if the disks are large :-(I''m under the impression that one has also to copy over corresponding files from /var/lib/xen/boot_kernel* and boot_ramdisk*, otherwise domU won''t reboot on the new dom0, but I still have to test this more systematically. -- To sto si frustriran, zavidan tko zna na cemu i sto ne vidis dalje od svoje guzice je tuzno. Da onda barem imas toliko samokontrole da sutis umjesto da pravis budalu od sebe... izgleda da si prestar da se promjenis na bolje. - Davor Pasaric, hr.comp.mac _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
xen-users-bounces@lists.xensource.com a écrit sur 20/05/2008 11:06:59 :> John Haxby <john.haxby@oracle.com> writes: > > > Rudi Ahlers wrote: > >> So, how does one move a domU from one physical server to another > >> physical server if there''s no shared storage in between? > >> > > > > Shut down or save the domU; copy the config and vbd files to the other > > server; start or restore the domU. > > > > Takes a while if the disks are large :-( > > I''m under the impression that one has also to copy over corresponding > files from /var/lib/xen/boot_kernel* and boot_ramdisk*, otherwise domU > won''t reboot on the new dom0, but I still have to test this more > systematically.Perhaps you''re right if you issue the "reboot" command from the domU or dom0 (I don''t test it). But if you do a "shutdown", then a "create", you don''t need boot files to follow the domU from one dom0 to the other. They are generated locally when the domU is xm created.> > -- > To sto si frustriran, zavidan tko zna na cemu i sto ne vidis dalje od > svoje guzice je tuzno. Da onda barem imas toliko samokontrole da > sutis umjesto da pravis budalu od sebe... izgleda da si prestar da se > promjenis na bolje. - Davor Pasaric, hr.comp.mac > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
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