Brining JBOD offline RAID drives back online

[toml]

I am trying to undue an extremely stupid mistake I did on a user’s Mac Pro machine.

The machine needed a firmware update. It had 2 500GB drives concatentated.

I realized that the firmware could not be installed booting from a RAID array. Thinking (not the best choice of verb in retrospect) I would split the RAID, update the firmware, and reconnect the RAID…I used the destroyRAID command. (it still hurts to type that) I have done no other manipulating since but boot from the install DVD and boot it into target disk mode.

The user had about 100GB of data. As I understand JBOD and Apple’s implementation of concatenate, there is no striping. So all of the data should be located on the first disk. The software raid info is stored on the drives so I am hoping it is still available and I can use it to restore the raid.

Here is the output from diskutil check and list when the mac pro is in target disk mode attached to my workstation:

RAID SETS
———
No RAID sets found

/dev/disk3
#: type name size identifier
0: GUID_partition_scheme *465.8 GB disk3
1: EFI 200.0 MB disk3s1
2: Apple_RAID_Offline 465.4 GB disk3s2
3: Apple_Boot 128.0 MB disk3s3
/dev/disk4
#: type name size identifier
0: GUID_partition_scheme *465.8 GB disk4
1: EFI 200.0 MB disk4s1
2: Apple_RAID_Offline 465.4 GB disk4s2
3: Apple_Boot 128.0 MB disk4s3

Have searched all types of boards most of the night for an answer but have come up dry. Please help…Thanks

Tom

[maccanada]

I’m honestly not one for kicking someone when they’re down, but I really don’t like any kind of RAID that doesn’t have redundancy – that is what the R in RAID stands for after all. Both RAID 0 and Concatenated Disk sets offer zero protection and really serve no purpose other than increasing the likelihood of disaster because when one compnent fails, everything goes.

For what it’s worth Apple does have a [url=http://docs.info.apple.com/article.html?artnum=304511]KB article[/url] telling you how to do the firmware update on a system booting from a software RAID set. Not that it’s an awful lot of use to you now.

Someone who’s looked into RAID headers may have something to add here, and I’d hazard a guess that that is all that needs to be fixed, but I don’t have any advice aside from getting on the phone to Drivesavers. Sorry.

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