Restrictions on recovering from duplicated catalog backups
Catalog backup capabilities
Prior to the release of NetBackup 6.5.4 it was only possible to make catalog backups to tape and BasicDisk storage. With the introduction of NetBackup 6.5.4 it is now possible to write the hot catalog backup to all disk types as well as tape. Full and partial catalog recovery to the original NetBackup environment is possible from the original copy created by the backup process in all cases.
With the introduction of NetBackup 6.5.4 it is also possible to duplicate hot catalog backups made to tape and disk types other than BasicDisk using storage lifecycle policies. However there are restrictions around the recovery from duplicated or replicated copies of the catalog backup.
There are four known restrictions to catalog backup/recovery in NetBackup 6.5.4 and 6.5.5, three of which have been resolved in subsequent releases. These restrictions can be summarized as follows:
- Catalog recovery from duplicated hot catalog backups (same domain) does not work - While duplication of the hot catalog backup under the control of a storage lifecycle policy is possible, it is not possible to perform a full catalog recovery from any copy other than the original (copy 1) using NetBackup 6.5.4 or 6.5.5. This restriction does not apply to NetBackup 6.5.6 and higher versions.
- Full or partial catalog recovery from replicated/mirrored disk based catalog backups (different domain) is not supported - It is not possible to duplicate catalog backups between domains under NetBackup control. Catalog backups written to replicating disk storage can be replicated to a disaster recovery domain 'out of band' (without NetBackup's knowledge) and, with appropriate manipulation of the DR file, a full or partial catalog recovery into the disaster recovery domain may be possible. However such a recovery is difficult to achieve and, even if successful, does not guarantee that other disk based backup images which have been replicated in the same way can be restored. For these reasons recovery of a replicated disk based catalog backup to another domain is not supported. This restriction is addressed by the nbcatsync command introduced in NetBackup 6.5.6 and 7.0.1 (this command is not available in NetBackup 7.0).
- Recovering disk based backup images in a different domain is not supported - Backup images stored on disk and replicated to a disaster recovery domain 'out of band' (without NetBackup's knowledge) may appear in the disaster recovery domain with different storage attributes to those recorded in the original NetBackup catalog. Because the mapping of the storage attributes in different domains cannot be guaranteed backup images replicated in this way must be imported to the disaster recovery domain using the bpimport command. Whether the catalog backup is stored on disk or tape, catalog recovery into another domain is supported only for accessing tape-based backup images. This restriction is addressed by the nbcatsync command introduced in NetBackup 6.5.6 and 7.0.1 (this command is not available in NetBackup 7.0).
- It is not possible to recreate a DR file by importing a catalog backup written to disk types other than BasicDisk - the command bpimport -drfile <id> -drfile_dest <location> does not work for disk media IDs. The value of -drfile must be either a tape media ID or a BasicDisk path. A solution to this restiction is still being developed.