[mythtv-users] Consequences of drive failure

[Michael Watson]

On 3/12/2012 7:19 PM, Simon Hobson wrote:
> tortise wrote:
>> Also the temp the drive is running at also seems relevant to me.  A
>> recent case change for me resulted in temp drops from ~ 52 degrees down
>> to ~ 32 degrees.  Got to be good for my drives, surely?!
>
>> One of my 2TB drives has suddenly got 516 bad sectors, should I replace
>> it asap?  (!)  I am considering how I copy it to a 3TB drive as a
>> replacement...
> Google did a report some years ago no looking at drive failures. Because fo the volumes they use, and the scale of monitoring, they were able to draw statistically significant conclusions. One of them was that temperature (within reason) didn't seem to affect drive lifetime.

In my experience, keeping the drive cooler does prolong its life.  I 
imagine google would be using enterprise grade drives, maybe that makes 
a difference.

>
> As to copying your drive, my technique is this :
> Install the new drive in the system along side the existing one - you can now let the system continue running as normal.
> Partition & format as required, mount somewhere on the filesystem. Use rsync to copy the recordings from the old drive to the new one. You can do this in batches if you want, stopping before the backed has to do any Myth related work (eg recording or serving up frontends).
> When ready to make the switch, stop the backend, run the rsync copy again to get the replacement drive fully up to date, make any changes that might be needed to fstab etc, shutdown, remove the old drive and start up.
>
I would add the new drive, create filesystem and mount, add the new 
drive to the default storage group, and remove faulty drive from the 
storage group, so no new recordings will be written to the old drive, 
(but you will not be able to access the recordings on the old drive from 
within myth unless you create a new storage group with the old drive 
included).
     Copy the recordings over using rsync, but precede the rsync command 
with "ionice -c3", and let the copy run its course.  Once done, modify 
fstab to include new drive and remove the old drive, shutdown and 
physically remove old drive.
     Power up, run find_orphans.py to clean up any missing recordings.