9.After the backup is complete and verified, unmount and delete the new file system and the logical volume you used for it.

10.Use the mklvcopy command to add back the logical volume copy you previously split off to the fslv logical volume.

11.Resynchronize the logical volume.

Once the mirror copy has been recreated on the logical volume, the syncvg command will resynchronize all physical partitions in the new copy, including any updates that have occurred on the original copy during the backup process.

It is always a good idea to check a backup for validity.

8.7.2 Using Events to Schedule a Backup

As described above, a crontab entry is often used for scheduling nightly backups during off-peak hours of the application. Now as you have several cluster nodes, each of them would need a crontab entry, in order to get its own data backed up. This crontab entry can determine whether only the “normal” data is backed up, i.e. the data this cluster node cares about during “normal” operations, or, in case of another’s node failure and a subsequent takeover of this node’s resources, backing up both of the cluster nodes’ data.

Whenever one node takes over the reources of another node, the

node_down_remote event has happened. You can use a post-event to the node_down_remote event to change the crontab entry from backing up only the local node’s data into backing up both nodes’ data.

Furthermore, if the second node eventually comes up again and takes its resources back, you will see a node_up_remote event in your logs. Thus, you can configure a post-event to the node_up_remote event to change the crontab entry back to the “normal” setting.

If you want to do a split-mirror backup, the crontab entry has to invoke a script, implementing the steps described above.

A more detailed description of this procedure can be found in the redbook HACMP/6000 Customization Examples, SG24-4498, Chapter 6.

8.8 User Management

As 2.7, “User ID Planning” on page 48 described, on an HACMP cluster, the administrator has to take care of user and group IDs throughout the cluster. If

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