Calling RAID experts, need help rebuilding RAID 5

2

[27]

n00b
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Apr 16, 2008
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I had an IOmega ix4 crash, the RAID 5 cant be rebuilt on teh NAS for some unknown reason, so I am trying to rebuild it on an Intel D975Xbx2 motherboard which also has a marvell (albeit different) chipset.

Currently Win7 sees all drives in disk management, although it doesnt show them in Computer because, I think, the file system is different since the ix4 uses a linux distro of some sort.

I tried using raid reconstructor, but it doesnt see the drives (makes sense since it isnt in "computer" at this point) so that doesnt work.

Is there some sort of software out there that might be able to rebuild this in windows... if not how would one do this in linux? (ive installed linux before, but couldnt navigate around worth an ish, so easiest way possible?)

Here is some background on what exactly happned if you want a read:

http://www.hardforum.com/showthread.php?t=1467269
 
I would suggest calling IOmega support.

Also, pull your data off now, before a second drive dies.
 
pjkenned said:
I would suggest calling IOmega support.

Also, pull your data off now, before a second drive dies.
Click to expand...

appreciate the input, but the NAS is dead. I've talked with their L3s and they have only seen this once before, the NAS can't rebuild the array. nor format it. i cant do anything with it lol

The whole point of the thread was to figure out how to get my data off..:D
 
What if you got another one? What did support say about placing the drives in another ix4? Some raid implementations do this fine. For example I just migrated a raid 1 and a raid 6 array from an Adaptec 31605 to a 5805 by simply moving the cables. The 5805 recognized the array no problem. Only other thing I had to do was to hit <enter> to accept the new configuration. Maybe a new ix4 would let you do something similar, however I would ask support first since you would be spending quite a few bucks if it didn't work.
 
@27

Sorry I only see your post today so below is a belated reply:
If the data is REALLY important to you, do not ever go into rushed self-induced response of any kind under such circumstances. I made that kind of errors years ago causing data loss that made some people very upset. Always try to keep yourself calm. I had experienced problems in the past that caused thousands people operation stopped two or three times and company-wide data loss and the highly unpleasant feeling of such encounter. (I moved on to other place already)

With that out of the way, now back to reality. If data must be recovered at all cost, I suggest data recovery firm (they usually ask you to stop everything immediately and ship the disks to them as-is to minimize further problem). However, seems you have already performed several attempts so the involved disks are likely no longer in original pristine condition, which complicates the problem further.

I have to put disclaimer 1st:

Use it at your own risk. I disclaim all responsibility. This is not a professional reference you can depend on.

Advice number 1 : EMC made the software for ix4. You can contact them for help if you want.

Advice number 2 : you must ignore entire post if other pro tell you ix4 is not based on linux md software raid. Obviously you should still seek help from vendors or EMC

0. If Data must be recovered, I still suggest DATA RECOVERY FIRM or EMC
1. If other pro steps forward, follow their advice. Remember I am not a pro. I am a user, not a developer nor engineering staff paid to fix the problem.

2. Below is a LAST HOPE response. I mean it. LAST HOPE.

2a. One potential problem with error recovery of RAID5 is, example below
2a-1. RAID-5 with 4 disks.
2a-2. 1 disk failed and removed. RAID-5 degraded. 3-disks active.
2a-3. 1 new disk installed, RAID-5 recovery started. One of the disk in the original 3 disk-set failed or went into deep error recovery(no-TLER). Array thought operation taking too long and dropped the disk. Now you have second disk failure in the middle of a recovery.

Some enterprise oriented expensive array controllers can address issues under many different failure scenario, even the one mentioned above. Simpler consumer oriented may or may not be able to deal with such scenario.

I am not sure what kind of situation you are in. Recently I encountered some mdadm issues. I run only RAID0 or RAID1, no RAID 5 experience.

IF this is standard Linux MD software RAID,
1. My understanding is you can pull all disks and put them into a standard desktop PC. (Make sure your PC power supply can handle the additional demand. You do not want to create additional problem related to PSU)
2. Make sure you record exactly what disk in what position 1/2/3/4. I know modern software should rebuild automatically without worry about position by design. I just feel safer this way. sorry :). This step refers to both ix4 and the desktop PC as well. Example for PC: record disk serial number, connect to sata port, use the smartctl to check whether the disk is correctly identified disk in the right port. SATA-0 maps to /dev/sda, sata-1 maps to /dev/sdb , etc. compare the serial number against disk in /dev/sda, ...
3. Leave the newly installed disk (the one that replaced the failed disk in ix4) out. Do not install this particular disk in desktop PC. Summary you should have 3-disks from the ix4 installed into desktop PC
4. To make sure you are not complicating your job, remove the diagnostic PC OS disk so only disks from ix4 are there.
5. Boot up with Live CD, example Fedora 12 LiveCD.
6. Fedora 12 LiveCD can detect Linux MD RAID-set automatically. You can see RAID disk icon when click and open Computer icon. To try to bring them online. double-click on the example RAID-5 disk icon. However, I suspect this is unlikely because you have performed too many operations after the 1st incident. Anyhow if luck is upon you, it will bring back the degraded array. Do not waste time, and do not try to reboot again to see whether you can do other thing, while the degraded RAID5 is still available, copy the data ASAP to other place through network.
6a. It is also my suspect that you probably cannot get any meaningful progress in step 6 and you need to drop to console/terminal at this point because there are likely errors trying to restart the MD RAIDSET. It is better doing this on command line so that you can see clearly what kind of response generated by system. You can try various options on command line but I will leave that to the mdadm expert in the forum.
7. If step 6-6a failed, shutdown, bring in the final disk ix4 disk (replacement disk) into desktop PC. Repeat steps 5-6-6a

I will give a further lower-level suggestion in another post if needed. Re-read this post several times to make sure you understand all the steps and additional command-line expectation if you wanted to do something based on it. I think there are some Linux mdadm users here so they can walk you through if needed.
 
Last edited:
@pjkenned
Tried another ix4 to no avail, we had the same issue.

@lightp2
The data itself is video and pictures of the kiddos, so while important it isnt going to kill anyone if I don't get the data back. I am just trying every effort to get it back that I can without breaking the bank.

Good news is I have some pretty good contacts over at EMC so I will try them tomorrow when I get back into the office. If they can't help I will be trying your other options

Thanks!

[27]
 
lightp2 said:
@27



2. Below is a LAST HOPE response. I mean it. LAST HOPE.



IF this is standard Linux MD software RAID,
1. My understanding is you can pull all disks and put them into a standard desktop PC. (Make sure your PC power supply can handle the additional demand. You do not want to create additional problem related to PSU)
2. Make sure you record exactly what disk in what position 1/2/3/4. I know modern software should rebuild automatically without worry about position by design. I just feel safer this way. sorry :). This step refers to both ix4 and the desktop PC as well. Example for PC: record disk serial number, connect to sata port, use the smartctl to check whether the disk is correctly identified disk in the right port. SATA-0 maps to /dev/sda, sata-1 maps to /dev/sdb , etc. compare the serial number against disk in /dev/sda, ...
3. Leave the newly installed disk (the one that replaced the failed disk in ix4) out. Do not install this particular disk in desktop PC. Summary you should have 3-disks from the ix4 installed into desktop PC
4. To make sure you are not complicating your job, remove the diagnostic PC OS disk so only disks from ix4 are there.
5. Boot up with Live CD, example Fedora 12 LiveCD.
6. Fedora 12 LiveCD can detect Linux MD RAID-set automatically. You can see RAID disk icon when click and open Computer icon. To try to bring them online. double-click on the example RAID-5 disk icon. However, I suspect this is unlikely because you have performed too many operations after the 1st incident. Anyhow if luck is upon you, it will bring back the degraded array. Do not waste time, and do not try to reboot again to see whether you can do other thing, while the degraded RAID5 is still available, copy the data ASAP to other place through network.
6a. It is also my suspect that you probably cannot get any meaningful progress in step 6 and you need to drop to console/terminal at this point because there are likely errors trying to restart the MD RAIDSET. It is better doing this on command line so that you can see clearly what kind of response generated by system. You can try various options on command line but I will leave that to the mdadm expert in the forum.
7. If step 6-6a failed, shutdown, bring in the final disk ix4 disk (replacement disk) into desktop PC. Repeat steps 5-6-6a

I will give a further lower-level suggestion in another post if needed. Re-read this post several times to make sure you understand all the steps and additional command-line expectation if you wanted to do something based on it. I think there are some Linux mdadm users here so they can walk you through if needed.
Click to expand...

Alright,

Talked with the EMC guys, they offered to replace the unit, although that doesnt get my data back... so im in the last ditch attempt before I fdisk these things.

So I burned the iso for Fedora 12, booted to it and it is NOT showing in computer, however disk utility is showing raid components...no idea where to go next.

screenshotcm.png
 
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