I have an AX-4 with a faulted disk.  It's Enlcosure 0, Disk 2 (10k, 146gb), which is in the Disk Processor Enclosure.  I have a replacement drive (10k, 300gb) for the SAN, but can I use it to replace the DPE disk?  There are 4 disks on the DPE that have a 'do not remove' graphic, thus my worry.

Here is my event log:

2015/05/25 00:45:15	0x720f	The storage system has disabled its write cache, most likely because of a hardware issue.
2015/05/25 00:45:09	0x7400	There are disk drives in this storage system that are not working properly.	Enclosure 0 Disk 2