21.2. Troubleshooting File Locks

In Red Hat Storage 2.0 you can use statedump command to list the locks held on files. The statedump output also provides information on each lock with its range, basename, PID of the application holding the lock, and so on. You can analyze the output to know about the locks whose owner/application is no longer running or interested in that lock. After ensuring that no application is using the file, you can clear the lock using the following clear lock command:
# gluster volume clear-locks VOLNAME path kind {blocked | granted | all}{inode [range] | entry [basename] | posix [range]}
For more information on performing statedump, see Section 13.5, “Performing Statedump on a Volume ”
To identify locked file and clear locks
  1. Perform statedump on the volume to view the files that are locked using the following command:
    # gluster volume statedump VOLNAME
    For example, to display statedump of test-volume: 
    # gluster volume statedump test-volume
Volume statedump successful
    The statedump files are created on the brick servers in the /tmp directory or in the directory set using server.statedump-path volume option. The naming convention of the dump file is <brick-path>.<brick-pid>.dump.
  2. Clear the entry lock using the following command:
    # gluster volume clear-locks VOLNAME path kind granted entry basename
    The following are the sample contents of the statedump file indicating entry lock (entrylk). Ensure that those are stale locks and no resources own them. 
    [xlator.features.locks.vol-locks.inode]
path=/
mandatory=0
entrylk-count=1
lock-dump.domain.domain=vol-replicate-0
xlator.feature.locks.lock-dump.domain.entrylk.entrylk[0](ACTIVE)=type=ENTRYLK_WRLCK on basename=file1, pid = 714782904, owner=ffffff2a3c7f0000, transport=0x20e0670, , granted at Mon Feb 27 16:01:01 2012

conn.2.bound_xl./gfs/brick1.hashsize=14057
conn.2.bound_xl./gfs/brick1.name=/gfs/brick1/inode
conn.2.bound_xl./gfs/brick1.lru_limit=16384
conn.2.bound_xl./gfs/brick1.active_size=2
conn.2.bound_xl./gfs/brick1.lru_size=0
conn.2.bound_xl./gfs/brick1.purge_size=0
    For example, to clear the entry lock on file1 of test-volume: 
    # gluster volume clear-locks test-volume / kind granted entry file1
Volume clear-locks successful
test-volume-locks: entry blocked locks=0 granted locks=1
  3. Clear the inode lock using the following command:
    # gluster volume clear-locks VOLNAME path kind granted inode range
    The following are the sample contents of the statedump file indicating there is an inode lock (inodelk). Ensure that those are stale locks and no resources own them. 
    [conn.2.bound_xl./gfs/brick1.active.1]
gfid=538a3d4a-01b0-4d03-9dc9-843cd8704d07
nlookup=1
ref=2
ia_type=1
[xlator.features.locks.vol-locks.inode]
path=/file1
mandatory=0
inodelk-count=1
lock-dump.domain.domain=vol-replicate-0
inodelk.inodelk[0](ACTIVE)=type=WRITE, whence=0, start=0, len=0, pid = 714787072, owner=00ffff2a3c7f0000, transport=0x20e0670, , granted at Mon Feb 27 16:01:01 2012
    For example, to clear the inode lock on file1 of test-volume: 
    # gluster  volume clear-locks test-volume /file1 kind granted inode 0,0-0
Volume clear-locks successful
test-volume-locks: inode blocked locks=0 granted locks=1
  4. Clear the granted POSIX lock using the following command:
    # gluster volume clear-locks VOLNAME path kind granted posix range
    The following are the sample contents of the statedump file indicating there is a granted POSIX lock. Ensure that those are stale locks and no resources own them. 
    xlator.features.locks.vol1-locks.inode] 
path=/file1 
mandatory=0 
posixlk-count=15 
posixlk.posixlk[0](ACTIVE)=type=WRITE, whence=0, start=8, len=1, pid = 23848, owner=d824f04c60c3c73c, transport=0x120b370, , blocked at Mon Feb 27 16:01:01 2012 
, granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[1](ACTIVE)=type=WRITE, whence=0, start=7, len=1, pid = 1, owner=30404152462d436c-69656e7431, transport=0x11eb4f0, , granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[2](BLOCKED)=type=WRITE, whence=0, start=8, len=1, pid = 1, owner=30404152462d436c-69656e7431, transport=0x11eb4f0, , blocked at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[3](ACTIVE)=type=WRITE, whence=0, start=6, len=1, pid = 12776, owner=a36bb0aea0258969, transport=0x120a4e0, , granted at Mon Feb 27 16:01:01 2012 
...
    For example, to clear the granted POSIX lock on file1 of test-volume: 
    # gluster volume clear-locks test-volume /file1 kind granted posix 0,8-1
Volume clear-locks successful
test-volume-locks: posix blocked locks=0 granted locks=1
test-volume-locks: posix blocked locks=0 granted locks=1
test-volume-locks: posix blocked locks=0 granted locks=1
  5. Clear the blocked POSIX lock using the following command:
    # gluster volume clear-locks VOLNAME path kind blocked posix range
    The following are the sample contents of the statedump file indicating there is a blocked POSIX lock. Ensure that those are stale locks and no resources own them. 
    [xlator.features.locks.vol1-locks.inode] 
path=/file1 
mandatory=0 
posixlk-count=30 
posixlk.posixlk[0](ACTIVE)=type=WRITE, whence=0, start=0, len=1, pid = 23848, owner=d824f04c60c3c73c, transport=0x120b370, , blocked at Mon Feb 27 16:01:01 2012 
, granted at Mon Feb 27 16:01:01 

posixlk.posixlk[1](BLOCKED)=type=WRITE, whence=0, start=0, len=1, pid = 1, owner=30404146522d436c-69656e7432, transport=0x1206980, , blocked at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[2](BLOCKED)=type=WRITE, whence=0, start=0, len=1, pid = 1, owner=30404146522d436c-69656e7432, transport=0x1206980, , blocked at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[3](BLOCKED)=type=WRITE, whence=0, start=0, len=1, pid = 1, owner=30404146522d436c-69656e7432, transport=0x1206980, , blocked at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[4](BLOCKED)=type=WRITE, whence=0, start=0, len=1, pid = 1, owner=30404146522d436c-69656e7432, transport=0x1206980, , blocked at Mon Feb 27 16:01:01 2012 

...
    For example, to clear the blocked POSIX lock on file1 of test-volume: 
    # gluster volume clear-locks test-volume /file1 kind blocked posix 0,0-1
Volume clear-locks successful
test-volume-locks: posix blocked locks=28 granted locks=0
test-volume-locks: posix blocked locks=1 granted locks=0
No locks cleared.
  6. Clear all POSIX locks using the following command:
    # gluster volume clear-locks VOLNAME path kind all posix range
    The following are the sample contents of the statedump file indicating there is all POSIX locks. Ensure that those are stale locks and no resources own them. 
    [xlator.features.locks.vol1-locks.inode] 
path=/file1 
mandatory=0 
posixlk-count=11 
posixlk.posixlk[0](ACTIVE)=type=WRITE, whence=0, start=8, len=1, pid = 12776, owner=a36bb0aea0258969, transport=0x120a4e0, , blocked at Mon Feb 27 16:01:01 2012 
, granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[1](ACTIVE)=type=WRITE, whence=0, start=0, len=1, pid = 12776, owner=a36bb0aea0258969, transport=0x120a4e0, , granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[2](ACTIVE)=type=WRITE, whence=0, start=7, len=1, pid = 23848, owner=d824f04c60c3c73c, transport=0x120b370, , granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[3](ACTIVE)=type=WRITE, whence=0, start=6, len=1, pid = 1, owner=30404152462d436c-69656e7431, transport=0x11eb4f0, , granted at Mon Feb 27 16:01:01 2012 

posixlk.posixlk[4](BLOCKED)=type=WRITE, whence=0, start=8, len=1, pid = 23848, owner=d824f04c60c3c73c, transport=0x120b370, , blocked at Mon Feb 27 16:01:01 2012 
...
    For example, to clear the all POSIX locks on file1 of test-volume: 
    # gluster volume clear-locks test-volume /file1 kind all posix 0,0-1
Volume clear-locks successful
test-volume-locks: posix blocked locks=1 granted locks=0
No locks cleared.
test-volume-locks: posix blocked locks=4 granted locks=1
You can perform statedump on test-volume again to verify that all the above locks are cleared.