If you are having difficulty upgrading the POSIX client, it might be due to a shared-memory-segment lock.
If the mapr-loopbacknfs service fails to start after an upgrade, use
the following steps to determine if a shared-memory-segment lock was the cause of
the failure:
loopbacknfs.log file. The loopbacknfs.log file is in
the following directory:
/usr/local/mapr-loopbacknfs/logs/
Create/Attach to shm failed
shmid of the
lock: ipcs -m | grep 0x0000161c
ipcrm -m <shm
id>
mapr-loopbacknfs service.