We have CX500 with 4 DAE expansion arrays in production environment. In one of the DAEs, disk 14 is configured as hot spare. Originally all the disks in all the DAEs were 136 GB disks but over a period of time we swapped them with higher capacity 300 GB disks. So I replaced disk 14 also with a 300 GB disk. (we do have two other hot spares in two other DAEs as well)
Recently Disk 14 was showing an amber light and under navisphere also it was showing as faulty, so I replaced with another 300GB disk. But the system did not identify the new disk and the light stays amber. While investigating, I noticed that if I do a right click on this particular DAE, I see an option "Bring Online" which I do not see any any other DAE.
Allthough all the LUNs created on RAID groups on this particular DAE are fine and the host does not have any problem.
My question is, Can I click on Bring Online? Will it cause any data crash on the disks on this array? OR should I plan an outage and shutdown the host server before selecting the Bring Online option?
Also, will it sense the replacement disk, once the array is online?