Starting mirrored protection
The Add Disk Unit and New Disk Pool wizards guide you through the process of adding pairs of similar capacity disk units to a protected disk pool. After your disk units are configured correctly, you are ready to start mirrored protection.
Mirrored protection is local to a single system and is distinct from cross-site mirroring. If you want to start mirroring on an independent disk pool that is unavailable, you can do so when your system is fully restarted. For all other disk pools, you must restart your system to dedicated service tools (DST) mode before you start mirror-protection.
There are restrictions to be aware of when you start mirror-protection on the disk units of a disk pool.
- Disk units that are device parity protected cannot be mirrored.
- Disk units must be mirrored to disk units that have the identical sector size.
- Disk units must be mirrored to disk units that have approximately the same capacity.
There are restrictions to follow when you start mirror-protection on the load source disk unit.
- The smaller capacity disk must start out as the load source device when two disks of unequal capacity are matched as a mirrored pair. The load source can then be matched with the larger capacity disk unit. For example, if the load source disk unit is a 35 G-Byte disk, it can be matched with a 36 GB disk. If the load source is a 36 G-Byte disk, it cannot be matched with the 35 G-Byte disk.
- The system must be directed to match the load source disk unit with a disk unit that is in a physical location the service processor cannot use to IPL the partition. From SST, select Work with disk units->Work with disk configuration->Enable remote load source mirroring. The Enable remote load source mirroring function allows a disk unit to be matched with the load source disk unit even though the disk unit is in a physical location the service processor is not able to use to IPL the partiton.
To start mirroring using your IBM® Navigator for i, follow these steps:
- Select Configuration and Service from your IBM Navigator for i.
- Select Disk Pools.
- Select the disk pool that you want to mirror.
- Right-click the disk pool that you want to mirror, and select Start Mirroring.