Removing disk units that have device parity protection from a disk pool with mirrored protection
This checklist shows the sequence of tasks that you use to remove one or more disk units from an IOA that is capable of device parity protection.
These tasks apply when the disk pools that contain the disk units have mirrored protection and when the disk units have device parity protection. Use these tasks when your are permanently removing disk units from your system. Do not use these tasks when you are repairing or replacing a failed disk unit. You must restart your system to the dedicated service tools (DST) mode to perform the tasks in this checklist.
When you perform the tasks in this checklist, the system moves large amounts of data. Make sure that you have completely saved your system in the event that you need to recover from an error situation.
Before you begin
Print a copy of this checklist. Check off the configuration tasks as you perform them. This checklist provides an important record of your actions. It may help you diagnose any problems that occur.
Most tasks in the checklist include links to other topics. Refer to these topics if you need more information about how to perform a particular task.
Task What to do Where to learn more 1.___ Display your current disk configuration. Evaluating the current configuration 2.___ Calculate the space requirements for the disk pools that are involved in disk removal. Calculating disk space requirements 3.___ Use option 21 from the Save menu to save your entire system. Save your system with the GO SAVE command 4.___ Restart your system and select the option to use dedicated service tools (DST). "How to Start Dedicated Service Tools (DST)" in Backup and Recovery. From the taskpad in iSeries™ Navigator, select Open iSeries Navigator Service Tools. 5.___ Remove disk units that you plan to remove from the system. Moving and removing disk units 6.___ Exclude the disk units from device parity protection. If you were successful in excluding the disk units, skip to task 9. Otherwise, continue to task 7. Excluding disk units from a parity set 7.___ Stop mirrored protection for the disk pools that will have disk units removed. When you stop mirrored protection, one disk unit from each mirrored pair becomes unconfigured. You need to stop mirrored protection only if the disk pool contains other disk units that are attached to the Input/Output Processor (IOP) and have device parity protection. Stopping mirrored protection 8.___ Stop device parity protection for all the disk units in the IOP. 9.___ Physically remove disk units. This is normally done by a service representative. If you stopped device parity protection in task 8, continue with task 10. If you did not stop device parity protection, skip to task 14. 10.___ Start device parity protection again. Starting device parity protection 11.___ Add unconfigured disk units to the correct disk pools. These disk units became unconfigured when you stopped mirrored protection in task 7. Adding a disk unit or disk pool 12.___ If you created a new disk pool on your system when you added disk units, the system set the storage threshold of the disk pool to 90%. If you want a different storage threshold for any disk pool, you can change it. Setting the threshold of a disk pool 13.___ Start mirrored protection for the disk pools that had mirrored protection stopped in task 7. Starting mirrored protection 14.___ Verify that your disk unit configuration is correct. Evaluating the current configuration 15.___ Print your disk configuration to have available in case a recovery situation occurs. Printing your disk configuration
Parent topic:
Disk protection checklists