On Fri, 2017-01-20 at 14:15 +0900, Rikimaru Honjo wrote: > Hi Cinder devs, > > I have a question about cinder. > Can I run cinder-volume and cinder-backup on a same host when I using > iscsi backend? > > I afraid that iscsi operations will be conflicted between cinder- > volume and cinder-backup. > In my understanding, iscsi operations are serialized for each > individual process. > But these could be raced between processes. > > e.g.(Caution: This is just a forecast.) > If cinder-backup execute "multipath -r" while cinder-volume is > terminating connection, > a multipath garbage will remain unexpectedly.
Hi, Before Mitaka it was *required* to place cinder-volume and cinder- backup on the same node. As both services shared same file lock directory, it was safe. In fact cinder-backup simply imported cinder- volume code. Since Mitaka cinder-backup doesn't do any iSCSI operations directly and attaches volumes by calling cinder-volume over RPC. This means that it's possible to place cinder-backup on other node than cinder-volume, but it's still totally safe to place them together. If you're able to reproduce a scenario that fails these assumptions, please file a bug report and we'll be happy to investigate and provide a fix. Thanks, Michal __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
