[LU-14714] allow starting with only MGS config log if local llog write fails

Related — Sat, 12 Aug 2023 05:48:16 +0000

It should be possible to mount an MDT or OST filesystem using only the MGS config llog if the local OSD filesystem is full. Currently the mount fails with -28 = -ENOSPC when it can't write a local copy of the config llog. This makes it impossible to mount the MDT/OST with Lustre and clean up space in a consistent manner without expert knowledge of the filesystem structure to do the cleanup when mounted as type ldiskfs.

mds02 kernel: LDISKFS-fs (dm-6): mounted filesystem with ordered data mode. Opts: user_xattr,errors=remount-ro,no_mbcache
,nodelalloc
mds02 kernel: LustreError: 5826:0:(osd_io.c:2172:osd_ldiskfs_write_record()) dm-6: error reading offset 0 (block 0, size 8192, offs 0), credits 29/29: rc = -28
mds02 kernel: LustreError: 5826:0:(llog.c:1419:llog_backup()) MGC10.10.1.17@o2ib: failed to backup log lfs1-MDT0001: rc = -28
mds02 kernel: LustreError: 5826:0:(mgc_request.c:1883:mgc_llog_local_copy()) MGC10.1.1.17@o2ib: failed to copy remote log lfs1-MDT0001: rc = -28
mds02 kernel: LustreError: 5989:0:(osp_sync.c:1524:osp_sync_init()) lfs1-OST0001-osc-MDT0001: can't initialize llog: rc = -28
mds02 kernel: LustreError: 5989:0:(obd_config.c:559:class_setup()) setup lfs1-OST0001-osc-MDT0001 failed (-28)
mds02 kernel: LustreError: 5989:0:(obd_config.c:1835:class_config_llog_handler()) MGC10.10.1.17@o2ib: cfg command failed: rc = -28
mds02 kernel: Lustre:    cmd=cf003 0:lfs1-OST0001-osc-MDT0001  1:lfs1-OST0001_UUID  2:10.10.1.19@o2ib  \x0a
mds02 kernel: LustreError: 15c-8: MGC10.10.1.17@o2ib: The configuration from log 'lfs1-MDT0001' failed (-28). This may be the result of communication errors between this node and the MGS, a bad configuration, or other errors. See the syslog for more information.

Whamcloud Community JIRA

[LU-14714] allow starting with only MGS config log if local llog write fails