Computer Associates BABWBN2900NE5 Clients Agents Guide - Page 45

UNIX, Linux, and Mac OS X Client Agent Configuration Snapshot and Direct I/O Support for UNIX UNIX client agents support the Snapshot and Direct I/O features. To take advantage of these features, one of the following environments must exist on the machine running the UNIX client agent: Feature Snapshot Platform Solaris Snapshot Direct I/O Direct I/O HP-UX 11.0 Solaris HP-UX 11.0 Software Requirements UFS file system with the fssnap package installed (Solaris 8 and 9) or the advanced version of VxFS file system. Advanced version of VxFS file system or Online Journaling File System (JFS). UFS file system or VxFS file system. Advanced version of VxFS file system or Online JFS. Snapshot and Direct I/O Descriptions With Direct I/O, the client agent takes a snapshot on advanced versions of VxFS, Online JFS (HP-UX), and UFS with fssnap installed on Solaris. The client agent mounts the snapshot to a temporary directory created in the root volume, and then generates the snapshot backup. After the snapshot backup is complete, the client agent dismounts from the temporary directory and deletes the snapshot. To perform a snapshot backup, you must specify a snapshot buffer. A snapshot buffer is the disk space used to store the original data before it is overwritten in the snapped volume. Remember these considerations when using the snapshot buffer: ■ The snapshot buffer needs to be large enough to store all the data that changes in the snapped volume for the duration of the backup. If the snapshot buffer runs out of space, the snapshot becomes invalid and the backup fails. ■ The snapped volume and the snapshot buffer should not be on the same file system. ■ For better performance, the snapped volume and the snapshot buffer should be on separate physical disks. ■ For UFS on the Solaris platform (using fssnap), the snapshot buffer can be a file name, a directory name, or a raw partition. Chapter 3: Adding and Configuring the Client Agents 45