Jim Henderson wrote:

> It sounds to me like they lack an understanding of "archival" vs. 
> "backup".

Precisely.

(There's also talk about how to "back up" our software so we don't lose it.)

Note also that there is a regulatory distinction between the two terms, 
and the government holds us to those regulations.

>>> 3. They want to keep the weeks' tapes in the server room until the end
>>> of the week.
>>>
>> Provide your observations about the potential risks to this choice, and
>> the benefits of alternatives.
> 
> ISTR this is typically done this so you could do restores of individual 
> files; if you needed to restore the entire system, you'd have to pull the 
> last full backup from offsite storage.  It depends on the value of the 
> data if its lost.

Actually it seems to be so they don't have to bother actually attending 
to the machine except once a week. To my mind, leaving all the tapes 
right next to the server rather negates the entire purpose of daily 
backups. If we're going to play that game, why not just only back up 
once a week?

[Yeah, I realise it's not *quite* the same, but you see what I'm saying.]

> Agreed.  That said, doing a restore is much better than depending on the 
> tape drive's report during the backup of problems.  I've been burned by 
> that - it said data was being written, but it was unreadable due to tape 
> errors.

Standard procedure is to record the data, rewind the tape, read back all 
the data and check it actually matches what's on disk, not just that the 
checksums on the tape are OK. Still, it seems reasonable to go a step 
further and actually test the thing "for real" by actually performing a 
backup. I'm not sure it needs to happen every 3 months though...

> Just Invis' description sounds like GFS style backups.  It's a style that 
> some people find difficult to describe.

Yeah, it's GFS. However, the chart they supplied seems to indicate that 
there is only one grandfather tape, only one father tape, and only one 
son tape. In other words, if you want to restore from 2 days ago, the 
tape has already been overwritten. Like, WTF? So clearly that can't be 
what they mean. Hey, it's not like anything is *labelled* or anything 
like that...

As I asserted, it probably made perfect sense to the guy who scribbled 
it down.

-- 
http://blog.orphi.me.uk/
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