Two-Minute Drill

Performing Scheduled Backups of an Unmounted File System

q	The ufsdump command supports full and incremental backups.
q	You can store the backup information (the dump level and the dump date) for a successfully backed up file system in the /etc/dumpdates file by using the -u option with the ufsdump command.
q	You can also issue the ufsdump command to get information rather than actually performing a backup. For example, the command with the S option estimates the amount of space in bytes needed to perform a backup.
q	The ufsdump command is used to back up whole file systems. You can use the cpio, pax, and tar commands to copy individual files (and file systems) to tapes.
q	You can use the dd command to copy files and file systems between disks.

Performing Backups of a Mounted File System

q	You can take a snapshot, of a mounted file system by using the fssnap command and then back up the snapshot onto an external device by using commands such as tar, cpio, or ufsdump.
q	The backing-store file destination must be on a file system separate from the file system that is being captured in the snapshot.

Restoring File System Backups

q	You can use the ufsrestore command to restore individual files or file systems.
q	The backup from a UFS snapshot can be restored just like any other backup by using the ufsrestore command.
q	The ufsrestore command can be used in the interactive mode by specifying the -i option.
q	You can delete UFS snapshots either by using the fssnap -d command or by rebooting the system. If you did not unlink the backing-store file at the time of taking the snapshot, you need to delete the backing-store file manually.