Removed multiple hardisks in RAID5 (Linux) and corrupted filesystem

jeetender · 07-25-2008, 01:45 AM

Hi

I have 4 Disk working on RAID5 with RHEL 4.6 Installed on a Dell 2950 server.
By mistake on running Linux to check if RAID is working or not, i removed two hardisk instead i should have removed one, which corrupted my linux filesystem.

I then shutdown the system, inserted the both disks which were withdrawn but it did not boot.

I even did fsck -r, it reparied plenty of files but no luck.
Please suggest what is the best way to repair the OS in cases like this.

Thanks

Pearlseattle · 07-25-2008, 05:40 AM

So, you mean you
1) shutdown the pc
2) removed the HDDs
3) started up the pc
4) shutdown the pc
5) reinstalled the HDDs
6) started up the pc => pc not booting (so you have raid5 as root, right?)

Not sure if it was a good idea to run a fsck -r.

Once 2 HDDs out of 4 failed because of my controller blowing up and the pc didn't want to recognize the raid5 anymore, and I was able to fix it and be able to access all the data with: (I then took a note of what I did

)

Quote:

If in a RAID array two HDDs or more fail / get an unhealthy status at the same time, there is the possibility that something might have gone wrong with the drivers of the controller. Try to restart the array with all the HDDs (e.g. a RAID 5 with 4 HDDs)...
mdadm --assemble --force /dev/md0 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1
...and check in "cat /proc/mdstat" if both the HDDs are still marked as "failed". If not, try to re-add the faulty HDD with...
mdadm --manage /dev/md0 --add /dev/sdd1
...or whichever HDD failed and see if the RAID rebuilds correctly and still works afterwards.

jeetender · 07-29-2008, 11:54 PM

Thanks Pearl.
I will try these steps and see if it works for me.

Thanks again!