[Tfug] Check file system and restore array

[Timothy D. Lenz]

Removed the failed drives mda1-3. Since there was a cable problem, I 
should have been able to add the drive back using:

sudo mdadm --manage /dev/md0 --remove /dev/sda1
sudo mdadm --manage /dev/md1 --remove /dev/sda2
sudo mdadm --manage /dev/md2 --remove /dev/sda3

Then zeroed the blocks using:

sudo mdadm --zero-superblock /dev/sda1
sudo mdadm --zero-superblock /dev/sda2
sudo mdadm --zero-superblock /dev/sda3

I started with sda3 adding back in using:

sudo mdadm --manage /dev/md2 --add /dev/sda3

It seemed to start ok. In the past I could add all 3 in right away, but 
when I tried the same thing for sda2, it waited for a bit. Then I got a 
bunch of errors on the screen one line each ending with a sector number. 
syslog seems to have more info.

http://pastebin.com/VLnXt5p7

Did I do something wrong? miss a steep? or is the drive in fact bad?

On 2/11/2013 4:31 PM, Nick Lopez wrote:
>    From your logs, a drive crapped out (repeated "media error"s). Replace it and move on. It's unclear why it didn't get dropped out of the MD array.
> As for removing the failed devices from the array, `mdadm md0 --remove failed`, same for md1 & md2. The notes you have for adding the replacement drive to the array look good, as well as the reinstalling of grub so it boots.
>
> For the NCQ, this isn't a driver or drive firmware bug that shows up as soon as you plug in the drive, so ignore it. NCQ is either not supported by your drive & controller or it is supported and works fine. Nothing needs to be done in either case.
>
>    From what you posted there is no reason to believe there is anything else wrong with the machine. Your bad recordings are just the system choking on the bad IOs and probably falling behind so you're getting a bitstream with missing pieces, like you would get with a bad incoming signal.
>
>     - nick
>
>
>
>
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