software raid on removable drives for backups

[Net Llama!]

On Thu, 3 Feb 2005, Jason Joines wrote:
> Net Llama! wrote:
> > On Wed, 2 Feb 2005, Jason Joines wrote:
> >>	My boss wanted to be able to retrieve data up to twelve weeks old even
> >>if one drive of a set died.  We were using RAID 5 with 4 drives.  We had
> >>several drive failures over the years they were in use but no data loss
> >>thanks to the RAID.
> >
> > i have to ask.  what kind of drives are you using, how many died, and over
> > how many years?  With just 4 drives, any more than a single drive failure
> > over ~3 years suggests a bigger issue.
> >
>
>
> 	It wasn't just four drives.  There were 6 sets of 4 drives and 1 set of
> 3 drives.  The 4 drive sets were for weekly and monthly backups and the
> 3 drive set was used for daily backups.  These were exported via NFS and
> backups were done to them via xfsdump, dump, tar, etc., depending on the
> situation.  Every week, the four drive sets were rotated out but the 3
> drive set was left in all the time.  So there were 27 drives total and
> at least 3 failed over the three year period, seems like there were more
> but I can't remember for sure.  They were all 80 GB Maxtor D540X drives.
>   So the schedule went like this.

Oh, so those were IDE, and not SCSI?  If so, then that failure rate sounds
about right.

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Lonni J Friedman                        netllama at linux-sxs.org
LlamaLand				http://netllama.linux-sxs.org