System Administration Guide: Devices and File Systems

Choosing the Type of Backup

You can perform full or incremental backups by using the ufsdump command. You can create a temporary image of a file system by using the fssnap command. The following table lists the differences between these types of backup procedures.

Table 23–4 Differences Between Types of Backups


Backup Type	Result	Advantages	Disadvantages
Full	Copies a complete file system or directory	All data is in one place	Requires large numbers of backup tapes that take a long time to write. Takes longer to retrieve individual files because the drive has to move sequentially to the point on the tape where the file is located. You might have to search multiple tapes.
Snapshot	Creates a temporary image of a file system	System can be in multiuser mode	System performance might degrade while the snapshot is created.
Incremental	Copies only those files in the specified file system that have changed since a previous backup	Easier to retrieve small changes in file systems	Finding which incremental tape contains a file can take time. You might have to go back to the last full backup.