Volume snapshot initialization failures occur when the Linux Agent performs an Advanced Open File Option (AOFO) snapshot of a Linux volume.

  • Modified Date:
  • Article ID:000084342


Snapshot initialization fails when Linux Agent attempts to perform Advanced Open File Option snapshot.  A possible job failure error could be:


Error Message


Linux Snapshot-Technology: An error occured while creating a snapshot for one or more Volumes.



Following are the possible causes and their corresponding solutions:
  1. Volume is already snapped: Consider the following scenarios and solutions:
    1. Scenario: The volume under consideration is already snapped by some other utility like Symantec System Recovery Linux Edition. 

      Solution: Stop the utility that has snapped the volume so that the target volume has been unsnapped and then re-try the snapshot-based backup.
    2. Scenario: The previous snapshot-based backup job was unable to unsnap the volume leaving the volume in a snapped state. When this occurs, the initializations of new snapshot-based backup jobs fail for those new snapshot-based backup jobs that try to back up files on the volume considered in a snapped state. 

      Solution: Stopping and then restarting the Linux remote agent daemon 'beremote' on the target Linux system may resolve the issue.
    3. Scenario: A current backup job's snapshot initialization of a volume can also fail if the same volume was snapped during a previous backup job but the unmounting of the volume fails.

      i. Volumes snapped by Linux AOFO snapshot-based backup jobs are mounted on: 

      ii. Dismounting of snapped volumes can fail if the following occurs: 
      Files or directories in "/opt/VRTSralus/.SymantecVolumeMounts" are being accessed using any other utility. 

      Solution: Stop the process that is accessing files or directories in “/opt/VRTSralus/.SymantecVolumeMounts". Stop and then restart the Linux Remote  Agent Daemon 'beremote', and then try the snapshot-based backup job again.
    4. Scenario: It is possible that the current working directory at one of the Linux terminals or process is "/opt/VRTSralus/.SymantecVolumeMounts" or one of its subdirectories. 

      Solution: Exit these directories, Stop and then restart the Linux Remote Agent Daemon 'beremote', and then try the snapshot-based backup job again.
  1.  Mounting of snapped volumes failed: Check for failures during execution of the mount command.
  2. Low memory conditions: If the Linux system is running low on available memory, the computer may not have enough memory available to snap the volume. To clear some memory that is used by the snapshot driver, run the following commands before the backup job starts:
    $ rmmod symbdsnap 
    $ modprobe symbdsnap
    $ echo 3 > /proc/sys/vm/drop_caches
  3. Cache file location: Check that the location specified for the Linux system cache file is not on a read-only volume, such as a write-protected drive.
  4. Volume space for cache file: Snapshot initialization can fail if the volume on which the cache file resides does not have enough available disk space. Cache size can be specified in "/etc/VRTSralus/ralus.cfg".
    The estimation of how much increase is required for the cache file size, is based on how much of the backup job actually completed.
    For example, if 80% of the selected files were backed up, it is possible that the cache file size was 20% which is too small. In this case, try increasing the cache file size by 25% as a safe estimate, and then retry the backup job
  5. Trying to snap an unsupported file-system: Snapshot creation using the Advanced Open File Option on Linux is supported only on volumes hosting ext-2, ext-3, ext-4, and reiserfs file systems. Snapshot initialization will fail if the snapshot-based backup job tries to snap a volume on any file system other than the file systems mentioned in the previous sentence.
  6. Trying to snap CD's, DVD's or mounted ISO image(s): The Linux Agent's Advanced Open File Option does not support backups of CD/DVD/and mounted ISOs. Snapshot initialization can fail if resources selected for backup contain CD/DVD file systems. To successfully back up using the Linux Agent's Advanced Open File System technology, do not select CD/DVD or mounted ISO file systems during the resource selection process.




Terms of use for this information are found in Legal Notices.



Did this article answer your question or resolve your issue?


Did this article save you the trouble of contacting technical support?


How can we make this article more helpful?

Email Address (Optional)