Hi Dhairya,
Sorry to resurrect this thread again, but we still unfortunately have an
issue with our filesystem after we attempted to write new backups to it.
We finished the scrub of the filesystem on Friday and ran a repair scrub
on the 1 directory which had metadata damage. After doing so and
rebooting, the cluster reported no issues and data was accessible again.
We re-started the backups to run over the weekend and unfortunately the
filesystem crashed again where the log of the failure is here:
https://www.mrc-lmb.cam.ac.uk/scicomp/data/uploads/ceph/ceph-mds.pebbles-s2.log-20240708.gz.
We ran the backups on kernel mounts of the filesystem without the
nowsync option this time to avoid the out-of-sync write problems..
I've tried resetting the journal again after recovering the dentries but
unfortunately the filesystem is still in a failed state despite setting
joinable to true. The log of this crash is here:
https://www.mrc-lmb.cam.ac.uk/scicomp/data/uploads/ceph/ceph-mds.pebbles-s4.log-20240708.
I'm not sure how to proceed as I can't seem to get any MDS to take over
the first rank. I would like to do a scrub of the filesystem and
preferably overwrite the troublesome files with the originals on the
live filesystem. Do you have any advice on how to make the filesystem
leave its failed state? I have a backup of the journal before I reset it
so I can roll back if necessary.
Here are some details about the filesystem at present:
root@pebbles-s2 11:49 [~]: ceph -s; ceph fs status
cluster:
id: e3f7535e-d35f-4a5d-88f0-a1e97abcd631
health: HEALTH_ERR
1 filesystem is degraded
1 large omap objects
1 filesystem is offline
1 mds daemon damaged
nobackfill,norebalance,norecover,noscrub,nodeep-scrub,nosnaptrim
flag(s) set
1750 pgs not deep-scrubbed in time
1612 pgs not scrubbed in time
services:
mon: 4 daemons, quorum
pebbles-s1,pebbles-s2,pebbles-s3,pebbles-s4 (age 50m)
mgr: pebbles-s2(active, since 77m), standbys: pebbles-s1,
pebbles-s3, pebbles-s4
mds: 1/2 daemons up, 3 standby
osd: 1380 osds: 1380 up (since 76m), 1379 in (since 10d); 10
remapped pgs
flags
nobackfill,norebalance,norecover,noscrub,nodeep-scrub,nosnaptrim
data:
volumes: 1/2 healthy, 1 recovering; 1 damaged
pools: 7 pools, 2177 pgs
objects: 3.24G objects, 6.7 PiB
usage: 8.6 PiB used, 14 PiB / 23 PiB avail
pgs: 11785954/27384310061 objects misplaced (0.043%)
2167 active+clean
6 active+remapped+backfilling
4 active+remapped+backfill_wait
ceph_backup - 0 clients
===========
RANK STATE MDS ACTIVITY DNS INOS DIRS CAPS
0 failed
POOL TYPE USED AVAIL
mds_backup_fs metadata 1174G 3071G
ec82_primary_fs_data data 0 3071G
ec82pool data 8085T 4738T
ceph_archive - 2 clients
============
RANK STATE MDS ACTIVITY DNS INOS DIRS CAPS
0 active pebbles-s4 Reqs: 0 /s 13.4k 7105 118 2
POOL TYPE USED AVAIL
mds_archive_fs metadata 5184M 3071G
ec83_primary_fs_data data 0 3071G
ec83pool data 138T 4307T
STANDBY MDS
pebbles-s2
pebbles-s3
pebbles-s1
MDS version: ceph version 17.2.7
(b12291d110049b2f35e32e0de30d70e9a4c060d2) quincy (stable)
root@pebbles-s2 11:55 [~]: ceph fs dump
e2643889
enable_multiple, ever_enabled_multiple: 1,1
default compat: compat={},rocompat={},incompat={1=base
v0.20,2=client writeable ranges,3=default file layouts on dirs,4=dir
inode in separate object,5=mds uses versioned encoding,6=dirfrag is
stored in omap,8=no anchor table,9=file layout v2,10=snaprealm v2}
legacy client fscid: 1
Filesystem 'ceph_backup' (1)
fs_name ceph_backup
epoch 2643888
flags 12 joinable allow_snaps allow_multimds_snaps
created 2023-05-19T12:52:36.302135+0100
modified 2024-07-08T11:17:55.437861+0100
tableserver 0
root 0
session_timeout 60
session_autoclose 300
max_file_size 109934182400000
required_client_features {}
last_failure 0
last_failure_osd_epoch 494515
compat compat={},rocompat={},incompat={1=base v0.20,2=client
writeable ranges,3=default file layouts on dirs,4=dir inode in
separate object,5=mds uses versioned encoding,6=dirfrag is stored in
omap,7=mds uses inline data,8=no anchor table,9=file layout
v2,10=snaprealm v2}
max_mds 1
in 0
up {}
failed
damaged 0
stopped
data_pools [6,3]
metadata_pool 2
inline_data disabled
balancer
standby_count_wanted 1
Kindest regards,
Ivan
On 28/06/2024 15:17, Dhairya Parmar wrote:
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On Fri, Jun 28, 2024 at 6:02 PM Ivan Clayson <ivan@xxxxxxxxxxxxxxxxx>
wrote:
Hi Dhairya,
I would be more than happy to share our corrupted journal. Has the
host key changed for drop.ceph.com <http://drop.ceph.com>? The
fingerprint I'm being sent is
7T6dSMcUUa5refV147WEZR99UgW8Y1qYEXZr8ppvog4 which is different to
the one in our /usr/share/ceph/known_hosts_drop.ceph.com
<http://known_hosts_drop.ceph.com>.
Ah, strange. Let me get in touch with folks who might know about this,
will revert back to you ASAP
Thank you for your advice as well. We've reset our MDS' journal
and are currently in the process of a full filesystem scrub which
understandably is taking quite a bit of time but seems to be
progressing through the objects fine.
YAY!
Thank you ever so much for all your help and please do feel free
to follow up with us if you would like any further details about
our crash!
Glad to hear it went well, this bug is being worked on with high
priority and once the patch is ready, it will be backported.
The root cause of this issue is the `nowsync` (async dirops) being
enabled by default with kclient [0]. This feature allows asynchronous
creation and deletion of files, optimizing performance by avoiding
round-trip latency for these system calls. However, in very rare cases
(like yours :D), it can affect the system's consistency and stability
hence if this kind of optimization is not a priority for your
workload, I recommend turning it off by switching the mount points to
`wsync` and also set the MDS config `mds_client_delegate_inos_pct` to
`0` so that you don't end up in this situation again (until the bug
fix arrives :)).
[0]
https://github.com/ceph/ceph-client/commit/f7a67b463fb83a4b9b11ceaa8ec4950b8fb7f902
Kindest regards,
Ivan
On 27/06/2024 12:39, Dhairya Parmar wrote:
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Hi Ivan,
The solution (which has been successful for us in the past) is to
reset the journal. This would bring the fs back online and return
the MDSes to a stable state, but some data would be lost—the data
in the journal that hasn't been flushed to the backing store
would be gone. Therefore, you should try to flush out as much
journal data as possible before resetting the journal.
Here are the steps for this entire process:
1) Bring the FS offline
$ ceph fs fail <fs_name>
2) Recover dentries from journal (run it with every MDS Rank)
$ cephfs-journal-tool --rank=<fs_name>:<mds-rank> event
recover_dentries summary
3) Reset the journal (again with every MDS Rank)
$ cephfs-journal-tool --rank=<fs_name>:<mds-rank> journal reset
4) Bring the FS online
$ cephfs fs set <fs_name> joinable true
5) Restart the MDSes
6) Perform scrub to ensure consistency of fs
$ ceph tell mds.<fs_name>:0 scrub start <path> [scrubopts] [tag]
# you could try a recursive scrub maybe `ceph tell
mds.<fs_name>:0 scrub start / recursive`
Some important notes to keep in mind:
* Recovering dentries will take time (generally, rank 0 is the
most time-consuming, but the rest should be quick).
* cephfs-journal-tool and metadata OSDs are bound to use a
significant CPU percentage. This is because cephfs-journal-tool
has to swig the journal data and flush it out to the backing
store, which also makes the metadata operations go rampant,
resulting in OSDs taking a significant percentage of CPU.
Do let me know how this goes.
On Thu, Jun 27, 2024 at 3:44 PM Ivan Clayson
<ivan@xxxxxxxxxxxxxxxxx> wrote:
Hi Dhairya,
We can induce the crash by simply restarting the MDS and the
crash seems to happen when an MDS goes from up:standby to
up:replay. The MDS works through a few files in the log
before eventually crashing where I've included the logs for
this here (this is after I imported the backed up journal
which I hope was successful but please let me know if you
suspect it wasn't!):
https://www.mrc-lmb.cam.ac.uk/scicomp/data/uploads/ceph/ceph-mds.pebbles-s3.mds_restart_crash.log
With respect to the client logs, are you referring to the
clients who are writing to the filesystem? We don't typically
run them in any sort of debug mode and we have quite a few
machines running our backup system but we can look an hour or
so before the first MDS crash (though I don't know if this is
when the de-sync occurred). Here are some MDS logs with
regards to the initial crash on Saturday morning though which
may be helpful:
-59> 2024-06-22T05:41:43.090+0100 7f184ce82700 10
monclient: tick
-58> 2024-06-22T05:41:43.090+0100 7f184ce82700 10
monclient: _check_auth_rotating have uptodate secrets
(they expire after 2024-06-22T05:41:13.091556+0100)
-57> 2024-06-22T05:41:43.208+0100 7f184de84700 1
mds.pebbles-s2 Updating MDS map to version 2529650 from mon.3
-56> 2024-06-22T05:41:43.208+0100 7f184de84700 4
mds.0.purge_queue operator(): data pool 6 not found in OSDMap
-55> 2024-06-22T05:41:43.208+0100 7f184de84700 4
mds.0.purge_queue operator(): data pool 3 not found in OSDMap
-54> 2024-06-22T05:41:43.209+0100 7f184de84700 5
asok(0x5592e7968000) register_command objecter_requests
hook 0x5592e78f8800
-53> 2024-06-22T05:41:43.209+0100 7f184de84700 10
monclient: _renew_subs
-52> 2024-06-22T05:41:43.209+0100 7f184de84700 10
monclient: _send_mon_message to mon.pebbles-s4 at
v2:10.1.5.134:3300/0 <http://10.1.5.134:3300/0>
-51> 2024-06-22T05:41:43.209+0100 7f184de84700 10
log_channel(cluster) update_config to_monitors: true
to_syslog: false syslog_facility: prio: info to_graylog:
false graylog_host: 127.0.0.1 graylog_port: 12201)
-50> 2024-06-22T05:41:43.209+0100 7f184de84700 4
mds.0.purge_queue operator(): data pool 6 not found in OSDMap
-49> 2024-06-22T05:41:43.209+0100 7f184de84700 4
mds.0.purge_queue operator(): data pool 3 not found in OSDMap
-48> 2024-06-22T05:41:43.209+0100 7f184de84700 4
mds.0.0 apply_blocklist: killed 0, blocklisted sessions
(0 blocklist entries, 0)
-47> 2024-06-22T05:41:43.209+0100 7f184de84700 1
mds.0.2529650 handle_mds_map i am now mds.0.2529650
-46> 2024-06-22T05:41:43.209+0100 7f184de84700 1
mds.0.2529650 handle_mds_map state change up:standby -->
up:replay
-45> 2024-06-22T05:41:43.209+0100 7f184de84700 5
mds.beacon.pebbles-s2 set_want_state: up:standby -> up:replay
-44> 2024-06-22T05:41:43.209+0100 7f184de84700 1
mds.0.2529650 replay_start
-43> 2024-06-22T05:41:43.209+0100 7f184de84700 1
mds.0.2529650 waiting for osdmap 473739 (which
blocklists prior instance)
-42> 2024-06-22T05:41:43.209+0100 7f184de84700 10
monclient: _send_mon_message to mon.pebbles-s4 at
v2:10.1.5.134:3300/0 <http://10.1.5.134:3300/0>
-41> 2024-06-22T05:41:43.209+0100 7f1849e7c700 2
mds.0.cache Memory usage: total 299012, rss 37624, heap
182556, baseline 182556, 0 / 0 inodes have caps, 0 caps,
0 caps per inode
-40> 2024-06-22T05:41:43.224+0100 7f184de84700 10
monclient: _renew_subs
-39> 2024-06-22T05:41:43.224+0100 7f184de84700 10
monclient: _send_mon_message to mon.pebbles-s4 at
v2:10.1.5.134:3300/0 <http://10.1.5.134:3300/0>
-38> 2024-06-22T05:41:43.224+0100 7f184de84700 10
monclient: handle_get_version_reply finishing 1 version
473739
-37> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: opening inotable
-36> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: opening sessionmap
-35> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: opening mds log
-34> 2024-06-22T05:41:43.224+0100 7f1847e78700 5
mds.0.log open discovering log bounds
-33> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: opening purge queue (async)
-32> 2024-06-22T05:41:43.224+0100 7f1847e78700 4
mds.0.purge_queue open: opening
-31> 2024-06-22T05:41:43.224+0100 7f1847e78700 1
mds.0.journaler.pq(ro) recover start
-30> 2024-06-22T05:41:43.224+0100 7f1847e78700 1
mds.0.journaler.pq(ro) read_head
-29> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: loading open file table (async)
-28> 2024-06-22T05:41:43.224+0100 7f1847e78700 2
mds.0.2529650 Booting: 0: opening snap table
-27> 2024-06-22T05:41:43.224+0100 7f1847677700 4
mds.0.journalpointer Reading journal pointer '400.00000000'
-26> 2024-06-22T05:41:43.224+0100 7f1850689700 10
monclient: get_auth_request con 0x5592e8987000 auth_method 0
-25> 2024-06-22T05:41:43.225+0100 7f1850e8a700 10
monclient: get_auth_request con 0x5592e8987c00 auth_method 0
-24> 2024-06-22T05:41:43.252+0100 7f1848e7a700 1
mds.0.journaler.pq(ro) _finish_read_head loghead(trim
231160676352, expire 231163662875, write 231163662875,
stream_format 1). probing for end of log (from
231163662875)...
-23> 2024-06-22T05:41:43.252+0100 7f1848e7a700 1
mds.0.journaler.pq(ro) probing for end of the log
-22> 2024-06-22T05:41:43.252+0100 7f1847677700 1
mds.0.journaler.mdlog(ro) recover start
-21> 2024-06-22T05:41:43.252+0100 7f1847677700 1
mds.0.journaler.mdlog(ro) read_head
-20> 2024-06-22T05:41:43.252+0100 7f1847677700 4
mds.0.log Waiting for journal 0x200 to recover...
-19> 2024-06-22T05:41:43.252+0100 7f1850689700 10
monclient: get_auth_request con 0x5592e8bc6000 auth_method 0
-18> 2024-06-22T05:41:43.253+0100 7f185168b700 10
monclient: get_auth_request con 0x5592e8bc6800 auth_method 0
-17> 2024-06-22T05:41:43.257+0100 7f1847e78700 1
mds.0.journaler.mdlog(ro) _finish_read_head loghead(trim
90131453181952, expire 90131465778558, write
90132009715463, stream_format 1). probing for end of log
(from 90132009715463)...
-16> 2024-06-22T05:41:43.257+0100 7f1847e78700 1
mds.0.journaler.mdlog(ro) probing for end of the log
-15> 2024-06-22T05:41:43.257+0100 7f1847e78700 1
mds.0.journaler.mdlog(ro) _finish_probe_end write_pos =
90132019384791 (header had 90132009715463). recovered.
-14> 2024-06-22T05:41:43.257+0100 7f1847677700 4
mds.0.log Journal 0x200 recovered.
-13> 2024-06-22T05:41:43.257+0100 7f1847677700 4
mds.0.log Recovered journal 0x200 in format 1
-12> 2024-06-22T05:41:43.273+0100 7f1848e7a700 1
mds.0.journaler.pq(ro) _finish_probe_end write_pos =
231163662875 (header had 231163662875). recovered.
-11> 2024-06-22T05:41:43.273+0100 7f1848e7a700 4
mds.0.purge_queue operator(): open complete
-10> 2024-06-22T05:41:43.273+0100 7f1848e7a700 1
mds.0.journaler.pq(ro) set_writeable
-9> 2024-06-22T05:41:43.441+0100 7f1847e78700 2
mds.0.2529650 Booting: 1: loading/discovering base inodes
-8> 2024-06-22T05:41:43.441+0100 7f1847e78700 0
mds.0.cache creating system inode with ino:0x100
-7> 2024-06-22T05:41:43.442+0100 7f1847e78700 0
mds.0.cache creating system inode with ino:0x1
-6> 2024-06-22T05:41:43.442+0100 7f1847e78700 2
mds.0.2529650 Booting: 2: replaying mds log
-5> 2024-06-22T05:41:43.442+0100 7f1847e78700 2
mds.0.2529650 Booting: 2: waiting for purge queue recovered
-4> 2024-06-22T05:41:44.090+0100 7f184ce82700 10
monclient: tick
-3> 2024-06-22T05:41:44.090+0100 7f184ce82700 10
monclient: _check_auth_rotating have uptodate secrets
(they expire after 2024-06-22T05:41:14.091638+0100)
-2> 2024-06-22T05:41:44.210+0100 7f1849e7c700 2
mds.0.cache Memory usage: total 588368, rss 308304, heap
207132, baseline 182556, 0 / 15149 inodes have caps, 0
caps, 0 caps per inode
-1> 2024-06-22T05:41:44.642+0100 7f1846675700 -1
/home/jenkins-build/build/workspace/ceph-build/ARCH/x86_64/AVAILABLE_ARCH/x86_64/AVAILABLE_DIST/centos8/DIST/centos8/MACHINE_SIZE/gigantic/release/17.2.7/rpm/el8/BUILD/ceph-17.2.7/src/include/interval_set.h:
In function 'void interval_set<T, C>::erase(T, T,
std::function<bool(T, T)>) [with T = inodeno_t; C =
std::map]' thread 7f1846675700 time
2024-06-22T05:41:44.643146+0100
ceph version 17.2.7
(b12291d110049b2f35e32e0de30d70e9a4c060d2) quincy (stable)
1: (ceph::__ceph_assert_fail(char const*, char const*,
int, char const*)+0x135) [0x7f18568b64a3]
2: /usr/lib64/ceph/libceph-common.so.2(+0x269669)
[0x7f18568b6669]
3: (interval_set<inodeno_t, std::map>::erase(inodeno_t,
inodeno_t, std::function<bool (inodeno_t,
inodeno_t)>)+0x2e5) [0x5592e5027885]
4: (EMetaBlob::replay(MDSRank*, LogSegment*, int,
MDPeerUpdate*)+0x4377) [0x5592e532c7b7]
5: (EUpdate::replay(MDSRank*)+0x61) [0x5592e5330bd1]
6: (MDLog::_replay_thread()+0x7bb) [0x5592e52b754b]
7: (MDLog::ReplayThread::entry()+0x11) [0x5592e4f6a041]
8: /lib64/libpthread.so.0(+0x81ca) [0x7f18558a41ca]
9: clone()
0> 2024-06-22T05:41:44.643+0100 7f1846675700 -1 ***
Caught signal (Aborted) **
in thread 7f1846675700 thread_name:md_log_replay
ceph version 17.2.7
(b12291d110049b2f35e32e0de30d70e9a4c060d2) quincy (stable)
1: /lib64/libpthread.so.0(+0x12cf0) [0x7f18558aecf0]
2: gsignal()
3: abort()
4: (ceph::__ceph_assert_fail(char const*, char const*,
int, char const*)+0x18f) [0x7f18568b64fd]
5: /usr/lib64/ceph/libceph-common.so.2(+0x269669)
[0x7f18568b6669]
6: (interval_set<inodeno_t, std::map>::erase(inodeno_t,
inodeno_t, std::function<bool (inodeno_t,
inodeno_t)>)+0x2e5) [0x5592e5027885]
7: (EMetaBlob::replay(MDSRank*, LogSegment*, int,
MDPeerUpdate*)+0x4377) [0x5592e532c7b7]
8: (EUpdate::replay(MDSRank*)+0x61) [0x5592e5330bd1]
9: (MDLog::_replay_thread()+0x7bb) [0x5592e52b754b]
10: (MDLog::ReplayThread::entry()+0x11) [0x5592e4f6a041]
11: /lib64/libpthread.so.0(+0x81ca) [0x7f18558a41ca]
12: clone()
We have a relatively low debug setting normally so I don't
think many details of the initial crash were captured
unfortunately and the MDS logs before the above (i.e. "-60"
and older) are just beacon messages and _check_auth_rotating
checks.
I was wondering whether you have any recommendations in terms
of what actions we could take to bring our filesystem back
into a working state short of rebuilding the entire metadata
pool? We are quite keen to bring our backup back into service
urgently as we currently do not have any accessible backups
for our Ceph clusters.
Kindest regards,
Ivan
On 25/06/2024 19:18, Dhairya Parmar wrote:
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On Tue, Jun 25, 2024 at 6:38 PM Ivan Clayson
<ivan@xxxxxxxxxxxxxxxxx> wrote:
Hi Dhairya,
Thank you for your rapid reply. I tried recovering the
dentries for the file just before the crash I mentioned
before and then splicing the transactions from the
journal which seemed to remove that issue for that inode
but resulted in the MDS crashing on the next inode in
the journal when performing replay.
The MDS delegates a range of preallocated inodes (in form of
a set - interval_set<inodeno_t> preallocated_inos) to the
clients, so it can be one inode that is untracked or some
inodes from the range or in worst case scenario - ALL, and
this is something that even the `cephfs-journal-tool` would
not be able to tell (since we're talking about MDS internals
which aren't exposed to such tools). That is the reason why
you see "MDS crashing on the next inode in the journal when
performing replay".
An option could be to expose the inode set to some tool or
asok cmd to identify such inodes ranges, which needs to be
discussed. For now, we're trying to address this in [0], you
can follow the discussion there.
[0] https://tracker.ceph.com/issues/66251
Removing all the transactions involving the directory
housing the files that seemed to cause these crashes
from the journal only caused the MDS to fail to even
start replay.
I've rolled back our journal to our original version
when the crash first happened and the entire MDS log for
the crash can be found here:
https://www.mrc-lmb.cam.ac.uk/scicomp/data/uploads/ceph/ceph-mds.pebbles-s3.flush_journal.log-25-06-24
Awesome, this would help us a ton. Apart from this, would it
be possible to send us client logs?
Please let us know if you would like any other logs file
as we can easily induce this crash.
Since you can easily induce the crash, can you share the
reproducer please i.e. what all action you take in order to
hit this?
Kindest regards,
Ivan
On 25/06/2024 09:58, Dhairya Parmar wrote:
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Hi Ivan,
This looks to be similar to the issue [0] that we're
already addressing at [1]. So basically there is some
out-of-sync event that led the client to make use of
the inodes that MDS wasn't aware of/isn't tracking and
hence the crash. It'd be really helpful if you can
provide us more logs.
CC @Rishabh Dave <mailto:ridave@xxxxxxxxxx> @Venky
Shankar <mailto:vshankar@xxxxxxxxxx> @Patrick Donnelly
<mailto:pdonnell@xxxxxxxxxx> @Xiubo Li
<mailto:xiubli@xxxxxxxxxx>
[0] https://tracker.ceph.com/issues/61009
[1] https://tracker.ceph.com/issues/66251
--
***Dhairya Parmar*
Associate Software Engineer, CephFS
<https://www.redhat.com/>IBM, Inc.
On Mon, Jun 24, 2024 at 8:54 PM Ivan Clayson
<ivan@xxxxxxxxxxxxxxxxx> wrote:
Hello,
We have been experiencing a serious issue with our
CephFS backup cluster
running quincy (version 17.2.7) on a
RHEL8-derivative Linux kernel
(Alma8.9, 4.18.0-513.9.1 kernel) where our MDSes
for our filesystem are
constantly in a "replay" or "replay(laggy)" state
and keep crashing.
We have a single MDS filesystem called
"ceph_backup" with 2 standby
MDSes along with a 2nd unused filesystem
"ceph_archive" (this holds
little to no data) where we are using our
"ceph_backup" filesystem to
backup our data and this is the one which is
currently broken. The Ceph
health outputs currently are:
root@pebbles-s1 14:05 [~]: ceph -s
cluster:
id: e3f7535e-d35f-4a5d-88f0-a1e97abcd631
health: HEALTH_WARN
1 filesystem is degraded
insufficient standby MDS daemons
available
1319 pgs not deep-scrubbed in time
1054 pgs not scrubbed in time
services:
mon: 4 daemons, quorum
pebbles-s1,pebbles-s2,pebbles-s3,pebbles-s4 (age 36m)
mgr: pebbles-s2(active, since 36m),
standbys: pebbles-s4,
pebbles-s3, pebbles-s1
mds: 2/2 daemons up
osd: 1380 osds: 1380 up (since 29m), 1379
in (since 3d); 37
remapped pgs
data:
volumes: 1/2 healthy, 1 recovering
pools: 7 pools, 2177 pgs
objects: 3.55G objects, 7.0 PiB
usage: 8.9 PiB used, 14 PiB / 23 PiB avail
pgs: 83133528/30006841533 objects
misplaced (0.277%)
2090 active+clean
47 active+clean+scrubbing+deep
29 active+remapped+backfilling
8 active+remapped+backfill_wait
2 active+clean+scrubbing
1 active+clean+snaptrim
io:
recovery: 1.9 GiB/s, 719 objects/s
root@pebbles-s1 14:09 [~]: ceph fs status
ceph_backup - 0 clients
===========
RANK STATE MDS ACTIVITY DNS INOS
DIRS CAPS
0 replay(laggy) pebbles-s3
0 0 0 0
POOL TYPE USED AVAIL
mds_backup_fs metadata 1255G 2780G
ec82_primary_fs_data data 0 2780G
ec82pool data 8442T 3044T
ceph_archive - 2 clients
============
RANK STATE MDS ACTIVITY DNS INOS
DIRS CAPS
0 active pebbles-s2 Reqs: 0 /s 13.4k
7105 118 2
POOL TYPE USED AVAIL
mds_archive_fs metadata 5184M 2780G
ec83_primary_fs_data data 0 2780G
ec83pool data 138T 2767T
MDS version: ceph version 17.2.7
(b12291d110049b2f35e32e0de30d70e9a4c060d2) quincy
(stable)
root@pebbles-s1 14:09 [~]: ceph health detail |
head
HEALTH_WARN 1 filesystem is degraded;
insufficient standby MDS
daemons available; 1319 pgs not deep-scrubbed
in time; 1054 pgs not
scrubbed in time
[WRN] FS_DEGRADED: 1 filesystem is degraded
fs ceph_backup is degraded
[WRN] MDS_INSUFFICIENT_STANDBY: insufficient
standby MDS daemons
available
have 0; want 1 more
When our cluster first ran after a reboot, Ceph ran
through the 2
standby MDSes, crashing them all, until it reached
the final MDS and is
now stuck in this "replay(laggy)" state. Putting
our MDSes into
debugging mode, we can see that this MDS crashed
when replaying the
journal for a particular inode (this is the same
for all the MDSes and
they all crash on the same object):
...
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay for [521,head] had [inode
0x1005ba89481
[...539,head]
/cephfs-users/afellows/Ferdos/20210625_real_DDFHFKLMT_KriosIII_K3/cryolo/test_micrographs/
auth fragtree_t(*^2 00*^3 00000*^
4 00001*^3 00010*^4 00011*^4 00100*^4 00101*^4
00110*^4 00111*^4
01*^3 01000*^4 01001*^3 01010*^4 01011*^3
01100*^4 01101*^4 01110*^4
01111*^4 10*^3 10000*^4 10001*^4 10010*^4
10011*^4 10100*^4 10101*^3
10110*^4 10111*^4 11*^6) v10880645 f(v0 m2024-06-22
T05:41:10.213700+0100 1281276=1281276+0) n(v12
rc2024-06-22T05:41:10.213700+0100 b1348251683896
1281277=1281276+1)
old_inodes=8 (iversion lock) | dirfrag=416
dirty=1 0x55770a2bdb80]
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay dir 0x1005ba89481.011011000*
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay updated dir [dir
0x1005ba89481.011011000*
/cephfs-users/afellows/Ferdos/20210625_real_DDFHFKLMT_KriosIII_K3/cryolo/test_micrographs/
[2,head] auth v=436385 cv=0/0 state=107374182
4 f(v0 m2024-06-22T05:41:10.213700+0100
2502=2502+0) n(v12
rc2024-06-22T05:41:10.213700+0100 b2120744220
2502=2502+0)
hs=32+33,ss=0+0 dirty=65 | child=1 0x55770ebcda80]
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay added (full) [dentry
#0x1/cephfs-users/afellows/Ferdos/20210625_real_DDFHFKLMT_KriosIII_K3/cryolo/test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fracti
ons_ave_Z124.mrc.teberet7.partial [539,head] auth
NULL (dversion
lock) v=436384 ino=(nil)
state=1610612800|bottomlru | dirty=1
0x557710444500]
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay added [inode 0x1005cd4fe35
[539,head]
/cephfs-users/afellows/Ferdos/20210625_real_DDFHFKLMT_KriosIII_K3/cryolo/test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_
005006_fractions_ave_Z124.mrc.teberet7.partial auth
v436384 s=0 n(v0
1=1+0) (iversion lock)
cr={99995144=0-4194304@538} 0x557710438680]
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.cache.ino(0x1005cd4fe35) mark_dirty_parent
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay noting opened inode [inode
0x1005cd4fe35 [539,head]
/cephfs-users/afellows/Ferdos/20210625_real_DDFHFKLMT_KriosIII_K3/cryolo/test_micrographs/FoilHole_27649821_Data_27626128_2762
6130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
auth
v436384 DIRTYPARENT s=0 n(v0 1=1+0) (iversion lock)
cr={99995144=0-4194304@538} | dirtyparent=1
dirty=1 0x557710438680]
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay inotable tablev 3112837 <=
table 3112837
2024-06-24T13:44:55.563+0100 7f8811c40700 10
mds.0.journal
EMetaBlob.replay sessionmap v 1560540883, table
1560540882 prealloc
[] used 0x1005cd4fe35
2024-06-24T13:44:55.563+0100 7f8811c40700 -1
/home/jenkins-build/build/workspace/ceph-build/ARCH/x86_64/AVAILABLE_ARCH/x86_64/AVAILABLE_DIST/centos8/DIST/centos8/MACHINE_SIZE/gigantic/release/17.2.7/rpm/el8/BUILD/ceph-17.2.7/src/include/interval_set.h:
I
n function 'void interval_set<T, C>::erase(T, T,
std::function<bool(T, T)>) [with T = inodeno_t;
C = std::map]'
thread 7f8811c40700 time
2024-06-24T13:44:55.564315+0100
/home/jenkins-build/build/workspace/ceph-build/ARCH/x86_64/AVAILABLE_ARCH/x86_64/AVAILABLE_DIST/centos8/DIST/centos8/MACHINE_SIZE/gigantic/release/17.2.7/rpm/el8/BUILD/ceph-17.2.7/src/include/interval_set.h:
568: FAILED ceph_assert(p->first <= start)
ceph version 17.2.7
(b12291d110049b2f35e32e0de30d70e9a4c060d2)
quincy (stable)
1: (ceph::__ceph_assert_fail(char const*,
char const*, int, char
const*)+0x135) [0x7f8821e814a3]
2:
/usr/lib64/ceph/libceph-common.so.2(+0x269669)
[0x7f8821e81669]
3: (interval_set<inodeno_t,
std::map>::erase(inodeno_t, inodeno_t,
std::function<bool (inodeno_t,
inodeno_t)>)+0x2e5) [0x5576f9bb2885]
4: (EMetaBlob::replay(MDSRank*, LogSegment*, int,
MDPeerUpdate*)+0x4377) [0x5576f9eb77b7]
5: (EUpdate::replay(MDSRank*)+0x61)
[0x5576f9ebbbd1]
6: (MDLog::_replay_thread()+0x7bb)
[0x5576f9e4254b]
7: (MDLog::ReplayThread::entry()+0x11)
[0x5576f9af5041]
8: /lib64/libpthread.so.0(+0x81ca)
[0x7f8820e6f1ca]
9: clone()
I've only included a short section of the crash
(this is the first trace
in the log with regards to the crash with a 10/20
debug_mds option). We
tried deleting the 0x1005cd4fe35 object from the
object store using the
"rados" command but this did not allow our MDS to
successfully replay.
From my understanding the journal seems okay as we
didn't run out of
space for example on our metadata pool and
"cephfs-journal-tool journal
inspect" doesn't seem to think there is any damage:
root@pebbles-s1 13:58 [~]: cephfs-journal-tool
--rank=ceph_backup:0
journal inspect
Overall journal integrity: OK
root@pebbles-s1 14:04 [~]: cephfs-journal-tool
--rank=ceph_backup:0
event get --inode 1101069090357 summary
Events by type:
OPEN: 1
UPDATE: 3
Errors: 0
root@pebbles-s1 14:05 [~]: cephfs-journal-tool
--rank=ceph_backup:0
event get --inode 1101069090357 list
2024-06-22T05:41:10.214635+0100 0x51f97d4cfe35
UPDATE: (openc)
test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
2024-06-22T05:41:11.203312+0100 0x51f97d59c848 UPDATE:
(check_inode_max_size)
test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
2024-06-22T05:41:15.484871+0100 0x51f97e7344cc
OPEN: ()
FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
2024-06-22T05:41:15.484921+0100 0x51f97e73493b
UPDATE: (rename)
test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc.teberet7.partial
test_micrographs/FoilHole_27649821_Data_27626128_27626130_20210628_005006_fractions_ave_Z124.mrc
I was wondering whether anyone had any advice for
us on how we should
proceed forward? We were thinking about manually
applying these events
(via "event apply") where failing that we could
erase this problematic
event with "cephfs-journal-tool
--rank=ceph_backup:0 event splice
--inode 1101069090357". Is this a good idea? We
would rather not rebuild
the entire metadata pool if we could avoid it (once
was enough for us)
as this cluster has ~9 PB of data on it.
Kindest regards,
Ivan Clayson
--
Ivan Clayson
-----------------
Scientific Computing Officer
Room 2N249
Structural Studies
MRC Laboratory of Molecular Biology
Francis Crick Ave, Cambridge
CB2 0QH
_______________________________________________
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To unsubscribe send an email to
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--
Ivan Clayson
-----------------
Scientific Computing Officer
Room 2N249
Structural Studies
MRC Laboratory of Molecular Biology
Francis Crick Ave, Cambridge
CB2 0QH
--
Ivan Clayson
-----------------
Scientific Computing Officer
Room 2N249
Structural Studies
MRC Laboratory of Molecular Biology
Francis Crick Ave, Cambridge
CB2 0QH
--
Ivan Clayson
-----------------
Scientific Computing Officer
Room 2N249
Structural Studies
MRC Laboratory of Molecular Biology
Francis Crick Ave, Cambridge
CB2 0QH
--
Ivan Clayson
-----------------
Scientific Computing Officer
Room 2N249
Structural Studies
MRC Laboratory of Molecular Biology
Francis Crick Ave, Cambridge
CB2 0QH
_______________________________________________
ceph-users mailing list -- ceph-users@xxxxxxx
To unsubscribe send an email to ceph-users-leave@xxxxxxx