Hi, I emailed about a week ago but did not get any response back This my second attempt. I understood that xm save -c (checkpointing feature) was included in Xen 3.1, but after taking days to have Xen running it seems that Xen 3.1 does not support VM (PVM or HVM) checkpointing. Is there any pseudo-stable version of Xen that supports checkpointing? cc _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
I don''t think I saw that email. 3.1 should support a checkpoint option for PVM, though it would need a helper script installed via the external-device-migrate xend option to checkpoint persistent storage. What exactly was the problem? On Sunday, 17 June 2007 at 13:35, Claris Castillo wrote:> > Hi, > I emailed about a week ago but did not get any response back This my > second attempt. > I understood that xm save -c (checkpointing feature) was included in Xen > 3.1, but after > taking days to have Xen running it seems that Xen 3.1 does not support VM > (PVM or HVM) > checkpointing. Is there any pseudo-stable version of Xen that supports > checkpointing? > > cc > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Well the problem is that I want to be able to ''checkpoint" a running VM periodically for a server availability experiment and I need some sort of documentation to even know if it is possible with Xen. I did not find anything in the documentation about this feature but I emailed the user list and I got a reply from Matt where he referred me to "xm save -c" BUT I have Xen 3.1 running on RHEL 5 and the manual page does not include any information about "xm save -c <vm> <savefile>". Am I missing something with Xen 3.1? In your email you mentioned "external-device-migrate". I just looked at the script and it does not seem to perform the checkpointing. Does this feature works similar to the one VMWare uses (REDELOG?). I know these kind of questions are more appropriate for the users-mailing list but for some reason Xen users don''t seem to be using the checkpointing feature at all (or nobody has ran into any issue with the feature --> which it is pretty good!) cc _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Sunday, 17 June 2007 at 14:02, Claris Castillo wrote:> Well the problem is that I want to be able to ''checkpoint" a running VM > periodically for > a server availability experiment and I need some sort of documentation to > even know if > it is possible with Xen. > > I did not find anything in the documentation about this feature but I > emailed the user list > and I got a reply from Matt where he referred me to "xm save -c" BUT I have > Xen 3.1 > running on RHEL 5 and the manual page does not include any information > about "xm save -c <vm> <savefile>". > Am I missing something with Xen 3.1?I guess the manual page wasn''t updated. xm save --help should mention the option.> In your email you mentioned "external-device-migrate". I just looked at > the script and it does not > seem to perform the checkpointing. Does this feature works similar to the > one > VMWare uses (REDELOG?).I don''t know how that feature works. xm save -c checkpoints the state of the VM memory and CPU to disk, but does not deal with disks. external-device-migrate is a hook to let you add in your own scripts to checkpoint disks when the guest is being checkpointed. The form of these scripts will depend on what kind of disks your domain is using (eg LVM or qcow). For an idea, I''ll attach some demo scripts I posted back in December. They aren''t meant to be deployed, but rather to give you an idea how you might checkpoint your own disks.> I know these kind of questions are more appropriate for the users-mailing > list but for some > reason Xen users don''t seem to be using the checkpointing feature at all > (or nobody > has ran into any issue with the feature --> which it is pretty good!)The feature could use some better docs. The wiki is probably a good starting point for them. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel