[ceph-users] Re: OSDs fail to start after stopping them with ceph osd stop command

We encountered the following problems while trying to perform maintenance on a Ceph cluster: The cluster consists of 7 Nodes with 10 OSDs each. There are 4 pools on it: 3 of them are replicated pools with 3/2 size/min_size and one is an erasure coded pool with m=2 and k=5. The following global flags were set: * noout * norebalance * nobackfill * norecover Then, after those flags were set, all OSDs were stopped via the command ceph osd stop, which seems to have caused the issue. After maintenance was done, all OSDs were started again via systemctl. Only about half of the 70 OSDs in total started at first - while the other half started, but got killed after a few seconds with the following log messages: ceph-osd[197270]: 2023-01-24T13:39:12.103+0100 7ff3fcf8d700 -1 osd.51 12161 map says i am stopped by admin. shutting down. ceph-osd[197270]: 2023-01-24T13:39:12.103+0100 7ff40da55700 -1 received  signal: Interrupt from Kernel ( Could be generated by pthread_kill(), raise(), abort(), alarm() ) UID: 0 ceph-osd[197270]: 2023-01-24T13:39:12.103+0100 7ff40da55700 -1 osd.51 12161 *** Got signal Interrupt *** ceph-osd[197270]: 2023-01-24T13:39:12.103+0100 7ff40da55700 -1 osd.51 12161 *** Immediate shutdown (osd_fast_shutdown=true) *** And indeed, when looking into the osd map via ceph osd dump, the remaining OSDs seem to be marked as stopped: osd.50 down out weight 0 up_from 9213 up_thru 9416 down_at 9760 last_clean_interval [9106,9207) [v2:10.0.1.61:6813/6211,v1:10.0.1.61:6818/6211] [v2:10.0.0.61:6814/6211,v1:10.0.0.61:6816/6211] exists,stop 9a2590c4-f50b-4550-bfd1-5aafb543cb59 We were able to restore some of the remaining OSDs via running ceph out osd XX ceph in osd XX and then starting the service again (via systemctl start). This did work for most OSDs, except for the OSDs that are located on one specific host. Some OSDs required several restarts until they did not kill themselves a few seconds after starting. This whole issue seems to be caused by the OSDs being marked as stopped in the OSD map [1]. Apparently this state should get reset when re-starting the OSD again [2], but for some reason this doesn't happen for some of the OSDs. This behavior seems to have been introduced via the following pull request [3]. We have also found the following commit where the logic regarding stop seemed to have been introduced [4]. We were looking into commands that reset the stopped status of the OSD in the OSD map, but did not find any way of forcing this. Since we are out of ideas on how to proceed with the remaining 10 OSDs that cannot get brought up: How does one recover from this situation? It seems like by running ceph osd stop the cluster got in a state that seems irrecoverable with the normal CLI commands available. We even looked into the possibility of manually manipulating the osdmap via the osdmaptool, but there doesn't seem to be a way to edit the start/stopped status and it also seems like a very invasive procedure. There does not seem to be any way we can see of recovering from this, apart from rebuilding all the OSDs - which we refrained from for now. Kind Regards Hanreich Stefan [1] https://github.com/ceph/ceph/blob/63a77b2c5b683cb241f865daec92c046152175b4/… [2] https://github.com/ceph/ceph/blob/63a77b2c5b683cb241f865daec92c046152175b4/… [3] https://github.com/ceph/ceph/pull/43664 [4] https://github.com/ceph/ceph/commit/5dbae13ce0f5b0104ab43e0ccfe94f832d0e1268 _______________________________________________ ceph-users mailing list -- ceph-users(a)ceph.io To unsubscribe send an email to ceph-users-leave(a)ceph.io