Troubleshooting MapR POSIX Client Upgrades

If you are having difficulty upgrading the MapR POSIX Client, it may be due to a shared memory segment lock.

If the mapr-loopbacknfs service fails to start after an upgrade, check if a shared memory segment lock was the cause of the failure using this procedure.

  1. Open the loopbacknfs.log file. The loopbacknfs.log file is in the following directory: /usr/local/mapr-loopbacknfs/logs/
  2. Check for the following string: Create/Attach to shm failed
  3. If the string exists perform the following steps:
    1. Run the following command to identify the shmid of the lock: ipcs -m | grep 0x0000161c
    2. Run the following command to remove the lock: ipcrm -m <shm id>
    3. Start the mapr-loopbacknfs service.