Adding hot spare using a disk from an existing RAID 5 string

OS's version is 7.2 and the machine is an 8202-E4D. The controller is a
2B4C and there are 8 19A1 disks in a RAID5 string.

The customer want to use one of the disks (occupation is around 39%) as an
hot spare.

The suggeste procedure is:

- remove a disk from the raid array
- format the disk
- start hot spare

Is that correct?

The procedure "Removing disk units that have device parity protection from
a disk pool without mirrored protection" in Disk management list some steps:
...
4 - Restart your system and select the option to use dedicated service
tools (DST).
5 - Remove disk units that you plan to remove from the system.
6 - Exclude the disk units from device parity protection. If you were
successful in excluding the disk units, skip to task 8. Otherwise, continue
to task 7.
7 - Stop device parity protection for all the disk units in the
Input/Output Processor (IOP).
8 - Physically remove disk units. If you stopped device parity protection
in task 7, continue with task 9. If you did not stop device parity
protection, skip to task 10.
9 - Start device parity protection again.
10- Verify that your disk unit configuration is correct.
...

I'm not confortable with point 6 (Otherwise, continue to task 7). "Stop
device parity" is that a common situation?


Thanks in advance for you suggestions / comments
--
Marco Facchinetti

Mr S.r.l.

Tel. 035 962885
Cel. 393 9620498

Skype: facchinettimarco