Mirroring system disks will protect the data when a physical disk on one side fails. However, data must be restored from backup data created in advance if the data is damaged due to a critical failure caused by multiple breakdowns and so on or by an operation mistake.
This section discusses the following content:
Necessary settings before and after backing up and restoring system disk.
For details, see "7.4.1 Settings Before Backing Up," "7.4.3 Settings After Backing Up," "7.4.4 Settings Before Restoring," and "7.4.7 Settings After Restoring."
Note
When the shared class or local class of GDS is used, the settings are necessary regardless of whether the system disk is mirrored by GDS.
Discusses the method of backing up data on a system disk to tape and the method of restoring data back to the system disk from tape. You must follow different restore procedures depending on whether or not the system can be booted.
For details, see "7.4.2 Backing Up [EFI]," "7.4.5 Restoring (When System Can Be Booted) [EFI]," and "7.4.6 Restoring (When System Cannot Be Booted) [EFI]."
Note
Data backed up before system disk mirroring cannot be restored back to the mirrored system disk.
If the system disk mirroring is once canceled and then configured again, you cannot restore the backed up data of the system disk that was collected when the system disk was mirrored previously.
For these reasons, by using this procedure, make sure to collect the backed up data of the system disk if the system disk mirroring is configured.
Also make sure to collect the backed up data of the system disk again if the system disk mirroring is configured again.
See
For backing up and restoring volumes (e.g. /opt, /home) other than system volumes (/, /usr, /var, /boot, /boot/efi, swap area) among volumes in the root class, see "7.6 Backup (Offline)", "7.7 Backup (by Slice Detachment)", "7.8 Backup (by Synchronization)", and "7.9 Backup (by OPC)."
