[Discuss] RAID question

[Murray Strome]

On 2016-04-30 08:31 PM, Patrick wrote:
> On Sat, 30 Apr 2016 20:01:14 -0700
> pw wrote:
>
>> GNU ddrescue.
>>
>> https://www.gnu.org/software/ddrescue/
> W00t!  Thanks, that looks just about right.  :-)  When the
> hardware arrives, I'll try producing a few deliberate errors
> and fixing them, to see what happens.
>
Have you thought of setting up your drives as ZFS?  I have set up a 
FreeNAS Network Attached Storage system with 5 hard drives as RAIDZ2 
which means that the files can be recovered if any two drives fail. 
Although none of the drives themselves have yet failed, I had some SATA 
cable issues that caused problems equivalent to two disks failing, and 
once I replaced the cables causing problems, all the data was recovered 
automatically. I built this using an old computer, and it seems to be 
working very well now. The FreeNAS OS is based upon Open BSD. In my 
case, it is on two 16GB USB drives (mirrored) so if (or should I say 
when, since it is inevitable) one fails, the system will still be 
operational, and the faulty one could be easily replaced.
There is a free training webinar available from FreeNAS.org which is 
repeated every weekday at 10:00AM PDT and which is updated frequently.

http://www.freenas.org/freenas-zfs-training/

Although you may not be interested in setting up a Network Attached 
Storage Server, a lot of the session is devoted to explaining ZFS and 
RAIDZ, so you might find it interesting.

Murray