Backup and restore

It is important to have a process for backing up your environment so that you can easily recover from a storage device failure or loss of data. In SAN File System, you must save both the file data and metadata together when you back up the global namespace. These are used to recreate your user data. You must also backup the system metadata, which is used to recreate the SAN File System configuration.

SAN File System does not provide backup and restore functionality; instead, it supports backup tools that are already present in your SAN environment. Depending on the type of failure, you might need to restore a single file, an older version of a file, a directory, a volume, or the entire system. SAN File System supports various options for protecting the system, including:
There are two basic methods available for backing up and restoring your data:

The file-based method saves and restores data at the file level. It uses the FlashCopy function or other third-party backup and restore application in your environment to back up or restore your user data. Use the file-based approach when files have been lost but the overall system remains healthy.

The volume-based method saves and restores data at the device level (that is, a "just-a-bunch-of-bytes" approach). To adopt the volume method, however, the actual copying and restoring of data must be provided as a service by the underlying storage subsystem. Use the volume-based approach when disaster strikes and the system, as well as the FlashCopy images, are unusable.

Tip: Your backup and restore process does not have to be centralized and homogenous, covering the entire SAN, although such a process simplifies the procedure. You can use the volume method even for a fragmented SAN that requires a piecemeal volume copy across two or more storage subsystems. In such a scenario, you would be responsible for manually managing those multiple backup sets as though they were a single backup set.

Parent topic: Concepts

Parent topic: Planning the backup and restore strategy

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