This TID is intended to provide a simple explanation of how to temporarily use NetWare mirroring to migrate data from one SAN to another.
First of all, it is important to understand that NetWare mirroring is done at the partition level. An NSS pool (or traditional volume) can consist of one or more NSS (or NetWare) disk partitions. In order to migrate the entire pool (or volume), you must first successfully mirror all partitions belonging to that pool (or volume) BEFORE you can disconnect the old SAN.
To migrate a single NSS pool which consists of two partitions:
1. Allocate enough disk space on the new SAN to contain all of the partitions of the data you will migrate from the old SAN
2. Initialize all LUNs from the new SAN which will contain the migrated data.
3. If the existing pools are part of a cluster, make sure that the new LUNs are all flagged Shareable for Clustering, then execute "cluster scan for new devices" from one node in the cluster.
4. Load NSSMU, if it is not already loaded, and select Partitions. If the pool is part of a cluster, this step MUST be performed on the node that has the pool active.
5. Highlight the first (or next) partition of the pool to be migrated (this will be on the old SAN), and select F3=Mirror
6. Select an item from the list of available free space on the new SAN, and press Enter
7. Toggle to the server console, and execute "mirror status"
8. Before going to the next step, wait until you see that the mirrored partitions are finished remirroring
9. Repeat steps 4 through 7 until all partitions belonging to the pool are 100% remirrored. If the pool is part of a cluster, you must not go to the next step until you execute "cluster scan for new devices" from the node that has the pool active.
10. Assuming that the LUN's on the old SAN do NOT contain partitons that belong to other pools, you can rezone the LUNs on the old SAN, so that the server(s) can no longer see them. A server reboot is probably the best way to verify that things are configured and working.
11. If you are still able to activate the pool, you can go to Step 12.
12. From the main menu of NSSMU, select "RAID Devices", and press Enter
13. You should now be on the RAID Devices screen. If so, highlight the first RAID device in the list, and press Enter. You should now be on the RAID Segments screen, and you should see two items listed. If you only see one item (on the RAID Segments screen) DO NOT DELETE it, just press Escape to go back to the RAID Devices screen, and continue with the next mirrored partition. If you do see two items on the RAID Segments screen, one of them should show a status of "Off Line". If so, highlight it and press "Delete". This will break the mrror for that partition, and take you back to the RAID Devices screen. Repeat Step 13 for each partition that belongs to the migrated pool.
This process is straight forward for one or two pools that have NOT been expanded across multiple LUNs. It is still possible to migrate data with the mirroring process on a much larger and complex scale, but it is more complicated, and will take longer to prepare for and perform. If you need additional help making sure everything is done correctly, please open a Support Request with Novell, and someone can help you sort things out.
Refer to KB 3776107 for How To Clean Up A Software Raid After Breaking the Mirror In NSSMU; i.e. Remove the mirrored flag from the now unmirrored single disk.