HP B6960-90078 manual Backing Up and Restoring Unix Specifics, VxFS Snapshot

Further Information

Backing Up and Restoring UNIX Specifics

Backing Up and Restoring UNIX Specifics

This section explains how to backup specific UNIX formats, including

VxFS, Enterprise Filesystems, and Context Dependent Filesystems.

VxFS Snapshot

What Is VxFS? VxFS allows you to back up a filesystem while it is being used by some other application. This is called an online backup and is done by creating a snapshot of a filesystem and backing up this snapshot.

You create a snapshot of a filesystem when you mount the VxFS filesystem to a temporary directory. At this point you also specify the filesystem you want to snap.

A snapshot is a copy of the filesystem at a specific moment in time you mount the VxFS filesystem to a temporary directory.

You can perform normal backups without using the VxFS snapshot feature by simply configuring a backup as for any other filesystem. In this case you cannot back up files that are in use.

You configure a backup of this temporary directory, which is actually a mountpoint to the snapshot of the filesystem as it was at the moment of the mount.

When the backup is finished, you unmount the snapshot filesystem so that it can be used for other purposes.

How to Configure If you want to use the VxFS online backup functionality, you must

VxFS Backup? configure the backup as follows:

1.You have to have an empty or unused partition created on your system that can be used by VxFS for a snapshot. See your system administrator’s manual for instructions.

The recommended size for the snapshot filesystem is up to 15% of the snapped filesystem, if the filesystem is used heavily use during the backup. Normally, the size should be around 5%.

Appendix A A-3