mirror of
https://github.com/ceph/ceph
synced 2024-12-29 23:12:27 +00:00
18 lines
911 B
ReStructuredText
18 lines
911 B
ReStructuredText
====================================
|
|
Kernel client troubleshooting (FS)
|
|
====================================
|
|
|
|
If there is an issue with the cephfs kernel client, the most important thing is
|
|
figuring out whether the problem is with the client or the MDS. Generally,
|
|
this is easy to work out. If the kernel client broke directly, there
|
|
will be output in dmesg. Collect it and any appropriate kernel state. If
|
|
the problem is with the MDS, there will be hung requests that the client
|
|
is waiting on. Look in ``/sys/kernel/debug/ceph/*/`` and cat the ``mdsc`` file to
|
|
get a listing of requests in progress. If one of them remains there, the
|
|
MDS has probably "forgotten" it.
|
|
We can get hints about what's going on by dumping the MDS cache:
|
|
ceph mds tell 0 dumpcache /tmp/dump.txt
|
|
|
|
And if high logging levels are set on the MDS, that will almost certainly
|
|
hold the information we need to diagnose and solve the issue.
|