I am apparently having trouble with the software RAID drive in my Mac Pro. Computer was making funny noises, so I rebooted. Upon checking Disk Utility, it is showing the following:
One of the RAID drives is showing up as a 3.9 Gb drive when it should be a 1.4 Tb drive with a RAID slice like the other one.
What's going on? Help!
Mac Pro, Mac OS X (10.5.8), 16 GB RAM
It sounds like one of the drives in the mirrored set has lost its mind (i.e., failed).
This is exactly the situation Mirrored RAID is good for.
Remove the failed drive, insert your spare drive of the same or larger size, and assign it as a spare. Then you should be able to get the RAID to rebuild onto the spare and bring it up to date in the next half-a-day or so. Then the mirror will show as working again.
Make sure your Backup is up-to-date. A second failure now (before the array has rebuilt) will give you data loss.
Thank you!
That single RAID will generally survive fine for a while, and you can shutdown and restart with little additional risk.
If you have been running short of space, you could get two new larger drives and use them to create a new, blank RAID. Then copy from the degraded set to a new, larger set.
How to repair a degraded mirrored RAID set.
