IBM Spectrum Scale (GPFS) Backups
You can back up and restore the data on a GPFS cluster.
The following backup types are available for GPFS data:
- Synthetic full
Note: We recommend that you run synthetic full backups with multiple streams, because synthetic full backups run as single-stream backups are slower. Also, if you run synthetic full backups with single stream, you cannot run restores with multiple streams and nodes. For more information on multiple-stream synthetic full backups, see Configuring Multiple Streams for Synthetic Full Backups.
GPFS snapshots preserve the file system at a point in time. With GPFS snapshots, you can perform scan and backup operations at the same time that you run user updates, and still obtain snapshots that are consistent with their point in time.
The scan phase creates GPFS snapshots of the subclient content and of all the independent filesets that are under the subclient content. Then, a GPFS scan that is based on the mmapplypolicy command runs on the snapshot paths. For example, if /gpfs1 is the subclient content and /gpfs1/dir1/fileset1 is an independent fileset under /gpfs1, then the scan creates one snapshot for /gpfs1 and one snapshot for /gpfs1/dir1/fileset1.
The path where the snapshots are created is visible on all the GPFS cluster nodes. The scan phase runs only on the master node.
The backup phase reads files from the snapshot. At the end of the backup phase, the master node deletes all the snapshots that were created.
Shared Job Results
All data access nodes that you include in backups must share the same Job Results directory. For information about changing the path of the Job Results directory, see Changing the Path of the Job Results Directory.
Note: All of the participating data access nodes must be at the same service pack level.