[LU-8152] show OST/MDT read-only status in "lctl dl" and/or "lfs df"

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.10.0
• Assignee: Jian Yu
• Reporter: Andreas Dilger

Description

To aid in debugging server problems when the filesystem has gone read-only, it would be useful to print "RO" for the device status in "lctl dl" instead of "UP", if that is possible without significant layering violations.

It would also be useful to print out the OS_STATE_DEGRADED and OS_STATE_READONLY flags with "lfs df", possibly one letter per flag [DR] after the device names, like:

$ lfs df
UUID                   1K-blocks        Used   Available Use% Mounted on
myth-MDT0000_UUID        9174328      584036     8066004   7% /myth[MDT:0]
myth-OST0000_UUID     3880285544  3451122460   235124108  94% /myth[OST:0] DR
myth-OST0001_UUID     3886052008  3362805556   328933836  91% /myth[OST:1]
myth-OST0002_UUID     3880285544  3547714164   216149060  94% /myth[OST:2] D
myth-OST0003_UUID     5840741952  3831815716  1716851948  69% /myth[OST:3]
OST0004             : inactive device

We might consider to require a -v flag if there is a concern that this would break the output format, but I don't think that it will.

Issue Links

• is related to: LU-8920 don't print permanently deactivated OSTs in lfs df output