Air Cleaner User Manual

Chapter 6. Offline Mirror Backups

SysBack reintroduces a new and enhanced SysBack Offline Mirror Backup

capability. This feature had previously been available as a separate option for

SysBack 4, but it is now included it at as a base function.

Purpose

Offline Mirror Backup allows you to split AIX mirrors. This allows user and

system access to one mirror copy while SysBack accesses the inactive copy for

backup operations. With the Offline Mirror Backup feature you can:

v Specify which mirror to split when there is more than one copy

v Specify the work directory for temporary work files

v Specify a Pre-offline user defined script which could be used to temporarily

quiesce mirrors before they are split. For example, this may be used to

temporarily halt a database before splitting mirrors in order to ensure data

integrity of the data backed up.

v Specify a user backup script, called a Backup Command File which is used to

execute the backup. You may also use this script to perform other actions like

restarting a database that was halted before the mirrors were split.

v Specify a Post-offline user defined script which could be used to perform

application tasks or other tasks as desired.

v Perform a Preview Offline Mirror Backup that will detect problems that would

prohibit mirrors from being split without actually starting the backup.

v List the items to be split at the volume group or the logical volume level

v Perform automated recovery or manual recovery for an interrupted Offline

Backup attempt.

Restrictions

Below is the list of restrictions to the SysBack Offline Mirror backup process:

v The Offline Mirror backup process can not backup data in JFS2 file systems at

this time due to an AIX limitation with the /usr/sbin/chfs command. Once

support for JFS2 has been added, SysBack will consider making the necessary

updates to support JFS2 at that time.

v When backing up data in file systems, unlike previous versions of the Offline

Mirror backup feature, the file systems must be mounted in order for the

mirrors to be split.

v There may not be any stale partitions in a logical volume specified to be split.

This must be rectified before attempting to split the logical volume. Using the

Preview option on the Offline Mirror backup process is a simple way to identify

stale partitions. Then, you may use native AIX command/usr/sbin/syncvg

command or the SysBack SMIT Menu Resynchronize Stale Partitions for a

Volume Group.