Identifying Failing Drive In RAID-0 Pair

[SickRick]

Tried this question in "Post-Install", perhaps I'll have better luck here (LOL).

Having one of my Sandisk SSD's on my Boot RAID-0 flaking on me.

Logging the following in system log:


May 19 00:26:59 Ricks-Mac-Pro kernel[0]: AppleRAID::completeRAIDRequest - error 0xe00002ca detected for set "HPro2R" (98846874-B4FC-4E46-9EFD-61C520E0CCCC), member 00291077-4A01-46DC-B810-9B4459B96CB6, set byte offset = 289809666048.
May 19 00:26:59 Ricks-Mac-Pro kernel[0]: disk3: I/O error.

How do I ID which of the two PHYSICAL DRIVES is going weird on me? The "disc3" is the RAID Volume itself, and I believe the "member" identifies which physical drive it is - but that number doesn't show up in "System Report", nor in any info provided by the "Info Button" in Disk Utility.

Kinda Scary - it started throwing errors backing up in TM and with CCC - but it seems to be getting through a CCC clone now. Reluctant to re-boot the system and reseat all drive cables/etc., until I'm sure I have a good CCC Clone.

At that point - I can ID which SSD is flaking on me - replace it - boot off a base install and CCC the clone'd drive to the newly created (from the replaced drive) RAID-0, and make it bootable again.

Thankfully - critical data is on a RAID-5, that backs up to another RAID-5 TM volume (and the occasional clone to a 4TB)...

Appreciate any assistance in ID'ing the flaking drive so I can replace it. Despite having a MacBook - this is my production box (never know how much you are dependent on your technology - until it is threatened).

Regards,

Rick

PS - the above was posted last night. I pulled the cover on my box and seated down the SATA cables - and was able to get an error-free backup - at which point, I shut down - blew the box out, unseated/re-seated both power & data on the drives - and it seems to be error-free at this point.

But it STILL would be nice to know (from a diagnostic standpoint) how to identify which PHYSICAL DRIVE is having issues on a logical (RAID) drive.

 

[SickRick]

Anyone?

Bueler?

Bueler?

To restate the question: How do can you identify the physical drive - from the member number listed in the system log?

Rick

 

[nobodynose]

Anyone?

Bueler?

Bueler?

To restate the question: How do can you identify the physical drive - from the member number listed in the system log?

Rick

Try "diskutil list" from the command line. You'll get a listing like this (mine doesn't contain a RAID, but I believe it will still list the RAID component drives separately:

/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *120.0 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Boot SSD                119.0 GB   disk0s2
   3:                 Apple_Boot Recovery HD             784.2 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *750.2 GB   disk1
   1:                        EFI                         209.7 MB   disk1s1
   2:                  Apple_HFS Users                   622.2 GB   disk1s2
   3:                  Apple_HFS Boot Shadow             126.9 GB   disk1s3
   4:                 Apple_Boot Recovery HD             784.2 MB   disk1s4

Now, once you've identified which drive partitions (diskxsy) comprise your RAID0, do a "diskutil info partition_name", where "partition_name" is the identifier given in the previous listing (disknsm). You'll see a listing like this, which includes a UUID (unique identifier) for the partition:

   Device Identifier:        disk0s2
   Device Node:              /dev/disk0s2
   Part of Whole:            disk0
   Device / Media Name:      Boot SSD


   Volume Name:              Boot SSD
   Escaped with Unicode:     Boot%FF%FE%20%00SSD


   Mounted:                  Yes
   Mount Point:              /
   Escaped with Unicode:     /


   File System Personality:  Journaled HFS+
   Type (Bundle):            hfs
   Name (User Visible):      Mac OS Extended (Journaled)
   Journal:                  Journal size 16384 KB at offset 0x37e000
   Owners:                   Enabled


   Partition Type:           Apple_HFS
   OS Can Be Installed:      Yes
   Media Type:               Generic
   Protocol:                 SATA
   SMART Status:             Verified
   Volume UUID:              [COLOR=#ff0000]017C79E6-8AE7-34BE-B767-F82E5AC0120E[/COLOR]


   Total Size:               119.0 GB (119040147456 Bytes) (exactly 232500288 512-Byte-Blocks)
   Volume Free Space:        64.8 GB (64822829056 Bytes) (exactly 126607088 512-Byte-Blocks)
   Device Block Size:        512 Bytes


   Read-Only Media:          No
   Read-Only Volume:         No
   Ejectable:                Yes


   Whole:                    No
   Internal:                 No
   Solid State:              Yes

You are looking for the Volume UUID (highlighted in red above). Find the one that matches the member UUID in the error message you're seeing, and I believe that will point you to the physical drive that's failing.

DISCLAIMER: I've never used Apple software RAID before, so I may have absolutely no idea what I'm talking about. But nothing I've suggested will make any changes to anything on your system, you're just listing information, so it should be harmless.