How to tell which failed drive is which LDEV
April 16, 2014
I have someone at a remote site that may need a drive replaced. How can I tell which drive is a certain LDEV?
Keven Miller, who at 3kRanger.com describes himself as "a software guy with a screwdriver," answers the question -- for those that don't have the benefit of seeing an amber light on a failed drive.
Well, for me, I run SYSINFO.PRVXL.TELESUP first. Then you have a map of LDEV# to SCSI path. Next, you have to follow your SCSI path via SYSINFO.PRVXL.TELESUP.
From the example above, on my 928, 56/52 is the built-in SCSI path. Each disk has a hardware selection via jumpers to set the address of 0 to 6. (7 is the controller). You would have to inspect each drive, which could be one of the two internal ones, or any external ones.
0/0/1/1.15 (intscsia.15) (I think top drive)
0/0/2/1.15 (intscsib.15) (I think bottom drive)
Plus an external, Ultra2 wide on 0/0/1/0
Narrow single ended on 0/0/2/0
slot-1 on 0/2/0
slot-2 on 0/4/0
slot-3 on 0/6/2
slot-4 on 0/6/0
Then, depending how the externals are housed, it could be just an address switch on the back of the housing case. Not sure about an N-Class, or a 9x7, or a 9x9. But the processes are the same. If you're running anything more complex, like RAID, a hardware guy will help.
Hardware guy Jack Connor of Abtech adds
There's the 12H, NIKE, VA family, and XP disc frames that are the common arrays.
Or, if it's not an array, but something like a Jamaica disc enclosure, you can look at SYSGEN>IO>LD to determine what all discs should be present, then do a :DSTAT ALL to see who's missing and record that path including the SCSI address.
You then would go the card that has the major path, such as 0/2/0/0, and then follow that cable to the Jamaica enclosure. Look at the back to determine from the dip switch setting what each slot's SCSI address is. That would be the failed drive.
Also, often times with a Jamaica enclosure the drive will have either a solid green light on or, alternatively, be totally dark while all the other drives see activity (with flashing green lights).