RAID1 disk errors - caused by bad disk and found by support of disk warrior/apple

I had a half year old MacPro with 2 Seagate 750 GB hard drives in a
RAID1 configuration (boot disk).
This disk developed bad errors, unrepairable by Disk Utility. On a
suggestion here I tried Disk Warrior.
Disk Warrior also had trouble, always hanging at step 9 (comparing the
new directory).
Alsoft's support led me through and finally concluded that the cause
must be in hardware. On their suggestion I tried MemTest, which
sometimes would only find half the RAM but otherwise found no trouble.
The computer also developed kernel crashes and video problems (these had
been seen before).
Apple Service found a defective hard disk (the originally supplied 160
GB Seagate Barracuda) and replaced it.
After that TechTool Pro, Memtest and Disk Warrior ran ok.
Alsoft helped me recover the RAID1, and it seems I did not loose much
data.

Nasty error, a defective disk introducing errors on the bus (this
probably led to the bad differences in the RAID1, faulty allocation
blocks, overlapped extents and such)!

Competent service though from both Alsoft and Apple.

Glad to have the server back up.

HTH

Marc

 

Well watch out, because faulty DISKS cannot cause problems in the
bus..but a faulty disk CONTROLLER can.