Exam Essentials

Know how to determine the number of tapes required to perform your backup. The number of tapes depends on the amount of data you have to back up. Run the ufsdump S /file_system command, where file_system is the file system you want to back up, and convert the number you get back (it's in bytes) to megabytes. Then, depending on the capacity of the tape you are using, you know how many tapes you need.

Understand the difference between full and incremental backups. Full backups back up all data within a file system. Incremental backups back up only the data that has been modified since the last lower-level backup.

Know how to perform full and incremental backups. Both types of backups are executed with the ufsdump command. The level of backup specified determines backup type. Level 0 is a full dump, and levels 1-9 are incremental backups.

Understand how to back up a file system by using a UFS snapshot. First, you take a snapshot of a mounted file system with the fssnap command. Then, using the snapshot as a virtual device, you use the ufsdump command to make a backup archive based on the snapshot.

Know how to restore backed up file systems. File systems backed up with the ufsdump command are restored with the ufsrestore command.

Know which situations call for a special case restoration. If you are restoring an entire file system, it will be a special case restoration. If you are restoring the root (/) or /usr file systems, there are even more steps involved.