re-mount two old disk from raid0 setup to recover data

I had setup two 500gb disk in RAID0 on my server, but recently suffered a hard disk failure (saw a S.M.A.R.T error on the HDD at boot). My host has put 2 new disk in RAID-0 again (re-installed the OS) and re-attached the old drives on the same machine, so that I can recover the data.

My old drives are:

/dev/sdb
/dev/sdc

How can I mount these two disks back in RAID0, so that we can recover the data from our old drive? Or is this not possible any more? Have I lost all my data?

This is my /etc/fstab and df -h

This is my fdisk -l:

[root@localhost ~]# fdisk -l

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00040cf1

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          13      102400   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2              13        1288    10240000   83  Linux
/dev/sda3            1288        2333     8388608   82  Linux swap / Solaris

Disk /dev/sdc: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005159c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1       60802   488385536   fd  Linux raid autodetect

Disk /dev/sdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0006dd55

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1          26      204800   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sdb2              26        4106    32768000   82  Linux swap / Solaris
/dev/sdb3            4106        5380    10240000   83  Linux
/dev/sdb4            5380       60802   445172736    5  Extended
/dev/sdb5            5380       60802   445171712   fd  Linux raid autodetect

Disk /dev/sdd: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x9f639f63

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1               1       60802   488385536   83  Linux

Disk /dev/md127: 956.0 GB, 955960524800 bytes
2 heads, 4 sectors/track, 233388800 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 524288 bytes / 1048576 bytes
Disk identifier: 0x00000000

I read somewhere that you can do this with this command: mdadm -A --scan however, it does not yield any result for me -> No arrays found in config file or automatically

Latheesan

Posted 2013-04-29T14:11:48.890

Reputation: 113

Two years later, and I found this discussion. In my case, I had two 1T RAID 1 drives from a decommissioned server that I plugged into a 2 bay dock. On Ubuntu 15.10, I ran mdadm - A --scan and, presto, a cluster was built allowing me full access to the data. I've upvoted the discussion. Thanks! – tim.rohrer – 2015-11-12T14:44:26.037

What is the output of mdadm --examine /dev/sdb and mdadm --examine /dev/sdc ? – Darth Android – 2013-04-29T14:14:28.657

Also, what is the output of cat /proc/mdstat ? – Darth Android – 2013-04-29T14:24:39.717

Just realized, you probably want to mdadm --examine the /dev/sdb5 and /dev/sdc1 partitions instead of the drives themselves. – Darth Android – 2013-04-29T14:36:00.197

I've examined it and here's the result: http://pastebin.com/raw.php?i=nnFzw0GG

– Latheesan – 2013-04-29T21:48:22.353

Uh, what's the output of cat /proc/mdstat ? That pastebin says that your old array is functioning just fine and is 100% clean - in fact, the reason you can't assemble the array is because it's already assembled. Try mkdir /mnt/oldData && mount /dev/md127 /mnt/oldData. That said, if one of the drives was giving a SMART error, I wouldn't trust the drive any more, and would still back up all of the data off of it. – Darth Android – 2013-04-29T22:42:43.820

Your new drives are not currently in RAID0. One drive is mounted to /, and the other drive is mounted to /vz – Darth Android – 2013-04-29T22:44:43.767

@DarthAndroid - This is the output of cat /proc/mdstat - http://pastebin.com/raw.php?i=7CcVSbQX

I am going to try and mount it and see if it works. Thanks for the suggestion.

– Latheesan – 2013-04-30T11:01:59.367

@DarthAndroid - I think you are right, our host has not even put 2 new disk back in RAID0, they literally put 1 disk and split it into two partition (one at / root and another at /vz ) - I will complain about this momentarily. My concern now is getting the data back. – Latheesan – 2013-04-30T11:03:56.767

@DarthAndroid - Thanks for recommending this mkdir /mnt/oldData && mount /dev/md127 /mnt/oldData - IT WORKED !!! – Latheesan – 2013-04-30T11:06:55.887

Awesome! I'd get a backup of the data moved to non-RAIDed disks ASAP, preferably even a local computer before your provider starts messing with the disks again, so that you're not at the mercy of their ability to do what they say. – Darth Android – 2013-04-30T16:29:15.700

This is exactly what I want to do right now; recover the data. I tried your reccomendation and I get the following error: mdadm: /dev/sdb5 is busy - skipping and mdadm: /dev/sdc1 is busy - skipping. I used mdadm to --examine sdb5 and sdc1 and this is what it says: http://pastebin.com/raw.php?i=nnFzw0GG

– Latheesan – 2013-04-29T21:47:23.053

re-mount two old disk from raid0 setup to recover data

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