Why Redhat Gluster Storage node goes into locked state ?

Issue

• Why Redhat Gluster Storage node goes into locked state ?

# cat var/log/glusterfs/etc-glusterfs-glusterd.vol.log |grep -i failed |tail
[2015-05-08 11:01:54.712627] E [glusterd-syncop.c:1014:_gd_syncop_commit_op_cbk] 0-management: Failed to aggregate response from  node/brick     <<===============
[2015-05-08 11:01:54.733252] E [glusterd-syncop.c:1204:gd_stage_op_phase] 0-management: Staging of operation 'Volume Status' failed on localhost : Volume a1278-tst-r2t01s01 is not started
[2015-05-08 11:02:55.037774] E [glusterd-syncop.c:1014:_gd_syncop_commit_op_cbk] 0-management: Failed to aggregate response from  node/brick
[2015-05-08 11:02:55.058981] E [glusterd-syncop.c:1204:gd_stage_op_phase] 0-management: Staging of operation 'Volume Status' failed on localhost : Volume a1278-tst-r2t01s01 is not started
[2015-05-08 11:04:55.634870] E [glusterd-syncop.c:1014:_gd_syncop_commit_op_cbk] 0-management: Failed to aggregate response from  node/brick

# cat var/log/glusterfs/etc-glusterfs-glusterd.vol.log |grep -i failed |wc -l
4183

[2015-05-08 11:04:55.656434] E [glusterd-syncop.c:1204:gd_stage_op_phase] 0-management: Staging of operation 'Volume Status' failed on localhost : Volume a1278-tst-r2t01s01 is not started    <<==============
[2015-05-08 11:05:56.040354] E [glusterd-syncop.c:1014:_gd_syncop_commit_op_cbk] 0-management: Failed to aggregate response from  node/brick
[2015-05-08 11:05:56.062190] E [glusterd-syncop.c:1204:gd_stage_op_phase] 0-management: Staging of operation 'Volume Status' failed on localhost : Volume a1278-tst-r2t01s01 is not started
[2015-05-08 11:06:15.667819] W [glusterd-op-sm.c:4017:glusterd_op_modify_op_ctx] 0-management: op_ctx modification failed
[2015-05-08 11:06:15.695901] E [glusterd-syncop.c:1204:gd_stage_op_phase] 0-management: Staging of operation 'Volume Status' failed on localhost : Volume a1278-tst-r2t01s01 is not started