User's Manual

hp StorageWorks File System Extender User Guide 187
HSM file system recovery is necessary in cases where the HSM file system is damaged and has not been
backed up, therefore it cannot be restored.
How it works
Limitations
• Recovery cannot properly handle user changes on an HSM file system that occurred after the last
migration is finished. To prevent this situation, you need to format the HSM file system.
• Symbolic links cannot be recovered because they are not migrated to FSE media.
• Recovery of Windows Alternate Data Streams (ADS) data is not supported, except for the names of
ADS, which are stored in NSC.
Prerequisite
• The Name Space Catalog (NSC) of the FSE partition whose HSM file system will be recovered must
exist.
Name Space Catalog (NSC) was introduced in the FSE release 2.1 and should have been created
during upgrade of the FSE software to that FSE release.
Linux specific
To recover an HSM file system on a Linux FSE client:
1. From the local /etc/fstab file, determine the device (block special device node) of the HSM file
system, and run the following command:
2. Format the HSM file system using the mkfs.ext3 command. For more information, refer to ”Creating
file systems on top of LVM logical volumes” on page 31 in the FSE Installation Guide.
3. Start the recovery of the HSM file system:
Windows specific
To recover an HSM file system on a Windows FSE client:
1. Using the fsepartition --show and mountvol commands, determine the corresponding volume
name and run the following command:
2. Format the HSM file system using Computer Management or the format command.
3. Unmount the HSM file system once again as described in step 1.
4. Start recovery of the HSM file system. Use the following command for this purpose:
Assuming the prerequisites are met, the recovery process will start recreating the file system structure as
follows:
1. The recovery job checks if the recovery has already been started so it can be resumed from the last
recovered fileID.
2. It verifies that the HSM file system is not mounted and then mounts it on the temporary mount point.
3. It removes the existing HSMDB.
4. It scans the FSC and recovers the file system.
5. The FSC scanner retains the last recovered file ID that is written in the recovery progress status file. This
enables file system recovery to be resumed after a power failure or other interruptions. In case this file
is lost, recovery is started from the beginning. If you want to start an interrupted recovery from the start,
you need to delete this file.
Linux specific
On Linux platform, the full pathname of the recovery progress status file is
/var/opt/fse/tmp/.PartitionName–_hsmfs_recover.
# umount Device
# fserecover --hsmfs PartitionName
C:\>fse --umount MountPoint VolumeName
C:\>fserecover --hsmfs PartitionName