On Tue, Dec 5, 2017 at 9:13 AM, Wido den Hollander <wido@xxxxxxxx> wrote: > >> Op 29 november 2017 om 14:56 schreef Jason Dillaman <jdillama@xxxxxxxxxx>: >> >> >> We experienced this problem in the past on older (pre-Jewel) releases >> where a PG split that affected the RBD header object would result in >> the watch getting lost by librados. Any chance you know if the >> affected RBD header objects were involved in a PG split? Can you >> generate a gcore dump of one of the affected VMs and ceph-post-file it >> for analysis? >> > > I asked again for the gcore, but they can't release it as it contains confidential information about the Instance and the Ceph cluster. I understand their reasoning and they also understand that it makes it difficult to debug this. > > I am allowed to look at the gcore dump when on location (next week), but I'm not allowed to share it. Indeed -- best chance would be if you could reproduce on a VM that you are permitted to share. >> As for the VM going R/O, that is the expected behavior when a client >> breaks the exclusive lock held by a (dead) client. >> > > We noticed another VM going into RO when a snapshot was created. When checking last week this Instance had a watcher, but after the snapshot/RO we found out it no longer has a watcher registered. > > Any suggestions or ideas? If you have the admin socket enabled, you could run "ceph --admin-daemon /path/to/asok objecter_requests" to dump the ops. That probably won't be useful unless there is a smoking gun. Did you have any OSDs go out/down? Network issues? > Wido > >> On Wed, Nov 29, 2017 at 8:48 AM, Wido den Hollander <wido@xxxxxxxx> wrote: >> > Hi, >> > >> > On a OpenStack environment I encountered a VM which went into R/O mode after a RBD snapshot was created. >> > >> > Digging into this I found 10s (out of thousands) RBD images which DO have a running VM, but do NOT have a watcher on the RBD image. >> > >> > For example: >> > >> > $ rbd status volumes/volume-79773f2e-1f40-4eca-b9f0-953fa8d83086 >> > >> > 'Watchers: none' >> > >> > The VM is however running since September 5th 2017 with Jewel 10.2.7 on the client. >> > >> > In the meantime the cluster was already upgraded to 10.2.10 >> > >> > Looking further I also found a Compute node with 10.2.10 installed which also has RBD images without watchers. >> > >> > Restarting or live migrating the VM to a different host resolves this issue. >> > >> > The internet is full of posts where RBD images still have Watchers when people don't expect them, but in this case I'm expecting a watcher which isn't there. >> > >> > The main problem right now is that creating a snapshot potentially puts a VM in Read-Only state because of the lack of notification. >> > >> > Has anybody seen this as well? >> > >> > Thanks, >> > >> > Wido >> > _______________________________________________ >> > ceph-users mailing list >> > ceph-users@xxxxxxxxxxxxxx >> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> >> >> >> -- >> Jason -- Jason _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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