Degraded mirrored raid- won't rebuild

I've had 2 500 gig drives mirrored. When I set up the drives I did not check "automatically rebuild".
I just discovered ( not too long after installing Leopard) that one slice was "damaged" and the raid was degraded. I tried to rebuild, but got an error message that said disk utility was unable to recognize the filesystem. I finally erased the "damaged" drive, verified it and am ready to try rebuilding the set, but don't want to lose data from the remaining drive from the original raid.
How should I proceed?
Thanks-
Ford

Well I'm sure VERY few people have multiples of EVERYTHING. I still have my data.
All I want to do is mirror a fresh drive with the other drive that was part of a mirrored raid set. That should be possible... it seems...
Please don't admonish me for not having more backups. I have a total of 1.25 terabytes of HD space with a lot of redundancy.

Similar Messages

How do I add a new drive to a degraded MIRRORED RAID set?

My mirrored raid said it was degraded because one of the drives had a failure.
Today I unplugged the faulty drive and inserted a new one.
So far so good.
I erased the new drive.
Then I went into disk utility and followed the instructions in the help about RAID but I cannot see how to add this new drive to the RAID.
I'm confused.
1) The data is all on the RAID (the good, original slice) so can I add a new slice?
2) how do I do it?
Many thanks

I don't recommend the Apple hardware RAID card, and it doesn't work with off the shelf drives. If you are using drives in RAID, first make sure they are RAID Edition or lacking that Enterprise. Same make/model/firmware.
If using Seagate, avoid anything prior to 7200.12 series. If WD the RE2/3 series.
Rebuilds are slow, and one reason why I recommend 3 drives, even if you lose one you are covered still.
Of course just having two backups per volume is more important and comes first; mirrors are great for live editing and recording (audio) but otherwise... I'd stick to stripe and redundant backups. Only if you need 24/7. Otherwise, forget mirror.

Offline Disc In Degraded Mirrored RAID Set

I have a 2 disc (300GB each) mirrored RAID set that has worked fine up until recently. One slice appeared failed so I attempted to rebuild it. 7 hours later it still showed up as failed. I attempted a rebuild once more and the same result. I then shut everything down and re-booted my whole system. Now the RAID set is still degraded but the slice now shows up as offline as opposed to failed.
I checked the connections and it's all connected fine.
I have run First Aid several times and no repairs were necessary.
Anyway I can get this back 'online'?
If not, can I delete it, repair it and if it's repaired add it back to the RAID set?

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.

Really Ignore Degraded Mirror RAID ?

Hi, I just became responsible for a studio with a RAID system -- I'm new to this so please bear with me.
Server Monitor shows that 2 drives are degraded. It seems that these are slices of a Type 1 (Mirror) RAID set. The symptoms match the following linked document exactly (which says Server Monitor may erroneously report degraded status of Journaled drive, and you can ignore if Disk Utility says it's OK):
http://docs.info.apple.com/article.html?artnum=107406
However, I can't say for sure that Disk Utility is giving me a green light on this RAID set. Disk Utility (the GUI application) says the RAID set and the slices are degraded. But Disk Verify comes through fine. Also "diskutil checkRAID" says that Status is Degraded but that both disks in set are "OK".
So do I worry about this or not?
Any and All Help Much APPRECIATED!

I have seen this issue on a couple of Xserve's
This is how I went about fixing-
Get someone in front of Xserve
Identify which one the 2 drives is NOT working IE- no blue activity light
Pull that drive and break RAID
Insert drive
Rebuild mirror, see this article for info-
http://docs.info.apple.com/article.html?artnum=106987
There is a way to rebuild the mirror in Disk Utility, I cannot find any info from Apple on this but i have used a few times.
On one Xserve I have done this at least 3 times, I have completely rebuilt the RAID and re-installed the OS and it still does it occasionally.
Ed

Destroyed mirror RAID (1), Want to get data, but how?

I had a degraded mirrored RAID set that was functioning in its degraded state - reads and writes were no problem.
I thought that if I used DiskUtility to destroy the RAID, it would convert the drives to normal drives, and I would have access to each individually, but this was not the case. I also thought the data was backed up, but this was not the case.
I used the minus sign in the RAID tab DiskUtility to destroy the RAID. There are now 2 drives, but neither is able to be mounted:
bash-3.2# diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUIDpartitionscheme *698.6 Gi disk0
1: EFI 200.0 Mi disk0s1
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
0: GUIDpartitionscheme *698.6 Gi disk2
1: EFI 200.0 Mi disk2s1
2: Apple_HFS 698.3 Gi disk2s2
If I try to verify the first disk:
bash-3.2# diskutil verifyDisk disk0
Error encountered attempting to verify/repair disk0: Unrecognized filesystem (-9958)
but if I try to mount it, it thinks the mount is successful, but nothing new shows up on the Desktop, nor with "df"
bash-3.2# diskutil mountDisk disk0
Volume(s) mounted successfully
in reality, the drive is NOT "mounted successfully."
disk2 is in worse shape, as the OS is not even fooled into thinking it is mountable:
bash-3.2# diskutil mountDisk disk2
One or more volume(s) failed to mount
So I am trying to put my recovery efforts toward disk0.
Any ideas on how to mount the drive and get data off of it?

I had the same issue a few months back.
1 drive of my mirroed raid died. So I took the working drive out of that box and put it in a FW enclosure. It mounted fine. However after converting it back to a regular volume it would not mount. I tried everything thing I exhausted google searches.
the only fix was to reinitialise the drive. Luckily I had the data backed up elsewhere.

Disk Utility gives error and does not rebuild mirrored RAID

After having a HDD fail on a mirrored RAID I replaced the HDD and attempted to rebuild. Disk Utility reports via Console that it can not find an Apple Boot partition to check size and then fails to repair the RAID. Details follow.
Mac OS X v.10.4.8 Server
Power Mac G3 (Blue & White)
512MB RAM
20GB ATA HDD – boot device on internal ATA bus
4x 160GB ATA HDDs - setup in RAID scheme on Sonnet ATA/133 PCI card
RAID configured using Mac OS X v.10.4.8's Disk Utility and is an Apple RAID version 2.
RAID scheme <from "diskutil checkRAID" cmd>:
Welcome to Darwin!
[myserver:~] myadminuser% diskutil checkRAID
RAID SETS
Name: Mirror_2
Unique ID: 5FF8AD5F-0892-482D-B430-C7069D63AFD2
Type: Mirror
Status: Online
Device Node: disk3
Apple RAID Version: 2
# Device Node UUID Status
0 disk0s3 1FB48B00-3E52-4C29-8F05-2ED8BDAE4544 Online
1 disk6s3 BF2E69C6-698E-4D6A-A2A9-FE8CDAD8A7B1 Online
Name: Mirror_1
Unique ID: B448A09D-EC10-41EE-BA45-4D4071A88EA5
Type: Mirror
Status: Degraded
Device Node: disk5
Apple RAID Version: 2
# Device Node UUID Status
1 disk2s3 09AD5705-CF67-48B3-8E31-79983BD4781A Online
0 disk4s3 23EB1952-8B18-4400-A6FE-22C2F707C097 Failed
Name: StorageRAID1
Unique ID: 2B8349AB-F553-4FD2-8440-C575791DA858
Type: Stripe
Status: Online
Device Node: disk7
Apple RAID Version: 2
# Device Node UUID Status
0 disk3 5FF8AD5F-0892-482D-B430-C7069D63AFD2 Online
1 disk5 B448A09D-EC10-41EE-BA45-4D4071A88EA5 Online
I configured this RAID scheme (two two drive mirrors striped together) according to this kbase document: http://docs.info.apple.com/article.html?artnum=304377
As shown in the above "diskutil checkRAID" output I have a failed HDD. So I replaced the HDD with another 160GB cold spare. I added the new drive to the mirror "Mirror_1" also known as disk5 and hit rebuild. Received the normal message that all data on the new drive I was adding would be erased.
I then receive the following error immediately in the Console Log:
Rebuilding RAID "Mirror_1"
2006-12-15 23:50:24.741 DiskManagementTool [375] WARNING: Could not find Apple Boot partition to check it's size, skipping disk5s-1s.
Rebuilding RAID slice "disk4s3"
Just to stem some confusion, the device ID disk4s3 has been used by the system for both the old failed HDD and the new replacement HDD.
The result of this attempted rebuild is I end up with all the data from Mirror_1 on the new HDD but the new HDD is not successfully added to the RAID, therefore Mirror_1 is still degraded and my problem not resolved.
I ran the appropriate rebuild cmd from both the GUI Disk Utility as described and from the CLI "diskutil repairMirror disk5 disk4s3" but no joy.
Any help would be greatly appreciated. This volume houses a large amount of important data including user home directories so while some offline time may be required data loss would not be very acceptable.
Thanks in advance and I will be happy to provide more information as necessary.

I guess doing it in Terminal would fail too:
diskutil repairMirror disk5 disk4

RAID degraded - mirrored striped volumes - how to see if mirroring is working

I've set up a mirrored raid drive. It keeps showing it as 'degraded', even though I've tested each disk separately and they come up OK.
What does it mean in this report by 'rebuilding'?
How do I sort out this 'degraded' status?
How can I tell if mirroring is working correctly?
The set up is:
===============================================================================
Name:                 Saturn
Unique ID:            CF319F64-987B-42FC-8C14-751766B37A49
Type:                 Mirror
Status:               Degraded
Size:                 8.0 TB (8000084869120 Bytes)
Rebuild:              manual
Device Node:          disk15
# DevNode   UUID                                  Status     Size
0 -none-    384CF206-BCD5-4804-BDB8-FF1C956EEF64 Online     8000084869120
1 -none-    F886018B-EEE1-4875-853E-BCD4298683F8 0% (Rebuilding)8000084869120
===============================================================================
Name:                 RAID0.1
Unique ID:            384CF206-BCD5-4804-BDB8-FF1C956EEF64
Type:                 Stripe
Status:               Online
Size:                 8.0 TB (8000219643904 Bytes)
Rebuild:              manual
Device Node:          -
# DevNode   UUID                                  Status     Size
0 disk14s2 78CEBE17-8AFA-4849-A5B2-B73D9906FFE2 Online     2000054910976
1 disk10s2 5D06DB08-6A3E-4041-A3F8-7E195D5B80DD Online     2000054910976
2 disk9s2   E430EC4F-AE2C-4B78-B2CC-04ED88315D3A Online     2000054910976
3 disk8s2   46EED2A6-BA53-4D54-8B69-FF5D650B97A0 Online     2000054910976
===============================================================================
Name:                 RAID0.0
Unique ID:            F886018B-EEE1-4875-853E-BCD4298683F8
Type:                 Stripe
Status:               Online
Size:                 8.0 TB (8000084901888 Bytes)
Rebuild:              manual
Device Node:          -
# DevNode   UUID                                  Status     Size
0 disk16s2 0B5223E9-2750-493B-A08E-01DD30E65065 Online     2000021225472
1 disk5s2   F473AEC5-34A0-444E-AE62-DE755ECCE8A5 Online     2000021225472
2 disk13s2 BDCBFE64-5771-4F3A-AECA-959B20844CD6 Online     2000021225472
3 disk11s2 63AF3296-C427-4805-9FB5-B496205F49E8 Online     2000021225472
===============================================================================

Hi,
As I known, RAID1, or mirroring, is the technique of writing the same data to more than one disk drive. Mirrors are usually used to guard against data loss due to drive failure. Each drive in a mirror contains
an identical copy of the data. No need to compare.
If the drive is bootable, You should have got a warning when you booted the machine saying that either drive 0 or drive 1 was corrupt/non-bootable/missing and then be given a choice to boot from the second drive.
Kate Li
TechNet Community Support

Xserve - Mirrored RAID Failed? Degraded? Confused...

Hi,
Can anyone shed some light on this situation please? Disk utility tells me one thing and Server Monitor tells me another.
I have an X-Serve with 3 drives and a Mirrored RAID Set running 10.5.8.
Server Monitor is showing a yellow status for disk 1 and disk 2. Raid Status: Degraded (Mirror) Pre-failure Warning: No Warnings
Disk Utility on the other hand shows that the Mirrored RAID sets are Degraded because disk2s4 = Failed and disk2s2 = Failed.
Running disk utility commands in terminal also show disk2s4 and disk2s2 as Failed.
I have not yet tried to Rebuild or eject / reconnect the disk. The only thing I've really done is some research and rebooted the server.
It sounds like disk 2 has failed. Is there any way to confirm it's dead? Are there any serious risks of trying to rebuild?
Thanks.
- F4st

I'm not sure why you think you're seeing conflicting information…
Server Monitor is showing a yellow status for disk 1 and disk 2. Raid Status: Degraded (Mirror) Pre-failure Warning: No Warnings
OK, So Server Monitor says the RAID is in a degraded state…
Disk Utility […] shows that the Mirrored RAID sets are Degraded because disk2s4 = Failed and disk2s2 = Failed
Running disk utility commands in terminal also show disk2s4 and disk2s2 as Failed
I don't see this is anything different. All three methods are telling you disk2 has failed and your mirror is relying on disk1 for all activity.
Is there any way to confirm it's dead?
Umm.. you mean other than Server Monitor, Disk Utility.app and diskutil?
Face it, it's dead. It's had it.
Are there any serious risks of trying to rebuild?
Sure. If the disk is dead, it's entirely possible that rebuilding the array on that disk will fail. You run the risk of a problem on disk1 and then all your data is gone.
My advice: Replace disk2 as soon as possible. If not sooner.

MacMini Mirror RAID degradated, 2nd slice failed

I have a Mac Mini Server Late 2012, with the following specs:
- 2.3 GHZ I7
- 10 GB RAM (1x2 GB, 1x8 GB)
- Dual 1 TB HD 5.400 RPM
- OSX Maverick 10.9.5
- Mirror RAID
Apparently an error with OwnCloud caused the disk to get almost full. I found the problem, deleted the files and then ran disk utility and, for my surprise, I found the raid hd (serverhd) marked as "degradated" and the 2nd disk marked as "failed":
Running diskutil on terminal confirms that the 2nd slice as "failed":
My questions are:
1. Does the failed status on disk1s2 means that the disk PHYSICALLY failed or that the data in the disk doesn't match with the one in the 1st disk?
2. If this is a data failure, how can I rebuild the data in the 2nd disk? By selecting the failed disk in disk utility and hitting Rebuild?
TIA
Victor Espina

I finally solved this issue:
1. Made a full copy of server's HD in a external disk using CCC
2. Changed boot drive to use the external disk. In theory, this was not needed but I prefered to boot from a different disk just in case.
3. Once booted from the external disk, when to Disk Utility and "demote" the failed disk from the RAID array.
4. Using Disk Utility, I reformated the failed disk and added again to the RAID set (to do this, select first the RAID set and then drag & drop the disk from the left panel)
5. Once the disk was added to the RAID set, I pressed Rebuild and waited until de RAID set was rebuilt.
6. Then I set the HD as the boot drive and restarted the server
Thanks all for your help on this.
Victor Espina

Rebuilding a Mirrored Raid using Disk Utility

I have a mirrored raid set up via disk utility. For some reason one drive was switched off recently so the 2 drives are now out of sync. Disk utility now says the raid is 'Degraded' with one of the slices marked as 'failed'
I can ignore this as the drive appears fine on the desktop. But I need it to be working correctly as a fully operating RAID.
If I click 'rebuild' it gives a warning saying 'Rebuilding a RAID set will destroy all information on the replacement disk “RAID Slice”.
SO- I'm assuming rebuild will correct the error and make it work but I'm concerned about this warning about destroying data! I assume it will simply copy everything from Drive A to the 'degraded' Drive B??
Thanks for any suggestions.

"SO- I'm assuming rebuild will correct the error and make it work but I'm concerned about this warning about destroying data! I assume it will simply copy everything from Drive A to the 'degraded' Drive B??"
This should indeed be the way it goes but since i do not have enough experience with that kind or RAID setup i strongly suggest backing up / cloning drive A to an external before doing the rebuild... just in case.

My mirrored RAID config shows degraded

My simple mirror RAID set is noted as degraded in Disk Utility, and one of the drives is doing frequent drive arm recalibrations. This drive set contains all my iTunes and iPhoto files. Time to replace a drive or two?
I'll copy the data to my desktop drive but then what?
- How do I diagnose which drive is the bad one?
- How do I know that in fact there is a bad one? Hard error or correctable soft error?
- How do I integrate a replacement drive in the set?
RAID Utility 1.0 and SoftRAID do not seem to apply to 10.3.9.
Searched the knowledgebase but no joy.
Any and all help w/b appreciated.
Regards, Mike

Well, I've tried just about every combination of Terminal/diskUtil(TR), Disk Utility(DU), reboot, and mount/re-mount that I can think of.
But it always comes to this:
1 - after the mirror is apparently rebuilt (before reboot) - DU reports both drives as degraded and TR checkmirror reports both OK. (Next, Pick 2, 3, or 4 for next step
2 - then rebooting OS X, TR checkmirror reports slice 0 as OK and slice 1 0%, and DU immediately starts rebuilding disk1s3 (disk 1 slice 3 - see how drive formatting breaks down from TR list). wash, rinse, repeat - see 1 (Oddly TR checkmirror shows both disks OK shortly after rebuild begins but well before completion.)
3 - After reboot and starting DU, it starts rebuilding immediately with no chance to cancel, I initially forced DU to stop by turning off the bad drive (it crashed actually with no disk error msg). Restarting DU and selecting the bad drive before the mirror (good half) mounted allowed me to reinitialize the bad drive. Then, selecting the mounted mirror and dragging the re-inited drive to the RAID box, I was able to select rebiuld and try it again. (Note - in the raid box after dragging the initialized drive, the good drive's status was "Forming" - I have no idea whether this was good or bad.) wash, rinse, repeat - see 1.
4 - After rebooting and skipping DU, using TR repairmirror gave same results (again TR checkraid noted both drives OK before completion). I eventually learned to wait until the drive busy lights (red glow surrounding the power on lite when writing) stopped - a couple of more hours. wash, rinse, repeat - see 1.
At this point I'm out of ideas/procedures. I guess the next step is to try to delete the mirror set, re-init both drives (to zeros), remirror them, and copy backup folders to the mirror.
Some notes for Mac developers in case they peruse this forum:
1. Please provide a desktop message when the mirror mounts if the mirror is degraded or when it goes bad during operations. Also report which drive(s) is(are) the culprit(s).
2. Provide the serial numbers in the diskutil list output. Also provide which disks are participating in the mirror as well as their status.
3. Provide better documentation of terms and processes. For example, to stop forcing a DU crash, I figured out that if I turned off the good mirror drive so it wouldn't mount, the bad drive would mount (dimmed) but could then be selected for re-inititlization.
4. Provide a cancel button on DU rebuilding progress box and include a time remaining bar.
This is pretty basic stuff. If Xserve is to go big time, RAID needs to be more robust in operation, and much more friendly to repair.
I have no idea how long I was operating with my data unprotected.
Any and all ideas welcome.
Thanks, Mike

Mirrored RAID taking too long for Data Rebuild

I have created a RAID 1 (Mirrored RAID) using Disk Utility in my Mac Pro. I have used 2 x 4TB WD Enterprise Grade HDDs. I copied 10 gb data on to this 4 TB RAID volume. Then removed one of the HDDs & installed in my other Mac Pro. It mounted as normal HDD & showed all the data that I had copied. To check if Disk Utility will rebuild the data, I deleted some part of this data (2 GBs out of 10 GBs) & installed this drive back in the system on which I had Created this RAID volume.
Initially I was surprised to find that Deleted data is now absent on this RAID volume. But on Launching Disk Utility it started rebuilding data on RAID volume.
BUT for Rebuilding 2 GB data estimated time shown by system was 9 hrs.
Is this NORMAL?
I intend to fill this 4 TB RAID volume with approximately 3.5 TB Data. In case one of the drive fails, how long should it take for Disk Utility to rebuild this amount of Data?
Is there any alternative way of speeding up this process?
Will Apple's RAID card help?
All your suggestions will be appreciated.
Thanks

I know this is an old thread but I'd be interested in what you came up with for a solution.
Here's my RAID journey thus far.
https://discussions.apple.com/message/25119317#25119317
Again, a gig of info and its taking 1 day 10 hours.
I hope theres a solution somewhere.
Drew

Mirrored RAID degraded, upper slice shows "failed" but drive passes verify

Hello,
I have a mid 2010 Mac Mini running Mountain Lion and Server. The Mirrored RAID is showing degraded and that the upper slice has failed. However, doing a verify of the drive does not report any problems.
Is there a way to determine if this is just a RAID management issue? I've considered rebooting into single user mode and running fsck but not sure what else it will tell me?
Is it safe for me to click on the slice that is showing "failed" and hit rebuitd? (after verifying a good back up of course). I started down this path but didn't like the warning OS X provided; it was not crystal clear which physical drive it would erease the data from.
Thanks,
Tim

I meant to add that boot up reports:
AppleRAIDSet: addMember() detected expired sequenceNumber (1) for member _______big id_____
AppleRAID::restartSet - restarting set "Harddrive name" (______another big id_____)
CoreStorage: fsck_cs has finished for group " ______yet another big id________" with status 0x00
CoreStorageFamily::unlockVEKs) failed to unwrap the vek, status = e00002bc
- Tim

Mirrorred RAID Rebuild Failing

Hello,
I had a mirrored raid setup on 10.6.7, everything was working great for the last month, then today I went into disk utility and it said one drive failed. After checking the drive, there didn't seem to be any problem with its operation, so I can only assume it was a software/communication failure.
Clicking the rebuild button resulted in this error:
Rebuilding RAID set failed with the error:
POSIX reports: The operation couldn't be completed. Operation not permitted.
So I tried removing a disk, that also failed with the same error.
I then erased the failed drive which automatically removes it from the RAID configuration. Now when I try to add it back to the configuration I get the exact same error.
Has any experienced this issue and have any suggestions on how to get RAID back online?
Thanks in advance!
Michael

Thanks for your reply.
Yes, I am sure that the drives are working. I do not know what caused one of the drives to 'fail' as far as disk utility was concerned - but it was online when I checked it again.
I had issues while originally creating the RAID configuration, similar POSIX issues.
I have managed to get the configuration back online using the SoftRAID, but I am unable to create any new RAID configurations or modify existing ones using Disk Utility. Is it possible its an issue with POSIX and the drive USB drivers? Though I have tried with 3 or 4 different brand drives.
SoftRAID allows the drive set to be converted to a Disk Utility set after creating/repairing it - so thats what I have done for now.
I will try to setup/repair this all again once I have Lion installed and see if they fixed it in that version.
Any suggestions on how to get Disk Utility's RAID configuration on a Intel Core 2 Duo Mac Mini would be appreciated. I have filed a bug report with Apple as well. SoftRAID was a suggested alternative to a few other posts on the discussions for similar issues.
Michael

Mirrored RAID set has degraded following power outage.

Hello,
Following a recent power outage our Mac Pro running Leopard OSX Server with 2 x 1TB discs in a Mirroring RAID configuration (with an installed RAID card) developed a 'severe error' message.
The Raid Set R0-1 has a Viable (degraded) status.
Drive One (or bay 1) is 'Good' and 'Assigned'
Drive Two is 'Good' but with the State - 'Roaming'
Also, the events display describes the failure of a drive 3 (there isn't one) and that the R0-1 is Degraded and no spare is available.
So, we're a little confused.
1. Is the Drive 2 no longer part of the RAID mirror (i.e. Roaming)
OR
2. Something more significant has happened hence the bogus Drive 3 message?
Any suggestions or advice would be much appreciated as always.
Thanks
Steve

Yes. Verification with the GUI tool is the first step. But... hmm, if you are dropping communications with the card, that is not a good sign. Make sure you have a backup and then try a PMU reset on the system. Maybe there is something wacky in the power manager. Then try any/all of these from Terminal to get more information:
raidutil list status
raidutil list eventinfo
raidutil list raidsetinfo
This should provide feedback. If these commands fail, then I fear that the card is not responding. Do you have AppleCare? It might be time to call for a replacement card.
Hope this helps

Degraded mirrored raid- won't rebuild

Similar Messages

Maybe you are looking for