On Thu, 31 Jul 2008 10:13:25 -0400, Tom Galvin wrote:

> Invisible wrote:
>> 
>> For anyone who's interested...
>> 
>> 1. They want to keep backup tapes (even differentials) forever. (No
>> regulations require this.)
>> 
>> 
> Ask why they want to do this.  You were not in the meeting where they
> decided to do this.  They should be happy to tell you.

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

>> 2. They want to allow the vagaries of the Gregorian calendar and its
>> lack of synchronisation with the 7-day week affect when our backups do
>> and don't happen.
> 
> Ask why?

I'm trying to remember if this is how the old Palindrome system worked - 
it used a Grandfather-Father-Son backup scheme that is common in the 
mainframe world, and while Palindrome used our calendar for its schedule, 
it may be a variation of this that doesn't is what they're using.

>> 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.

>> 4. They want to verify that tape restoration works by restoring a
>> standardised, unchanging 0.09 KB file and performing a visual
>> inspection to check that it "looks the same". (In fairness, if the
>> backup software says it's restored, you can be 99% sure it's fine.
>> Usually if there's a problem the software will complain that it "can't"
>> restore the file, rather than restore gibberish. But even so...)
>> 
> Be nice, and give constructive feedback.

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 (that was old DAT technology years ago, so the newer stuff is 
probably better, but I'd still trust at least a read with error checking 
of the tape over any reporting that comes back during the backup).

>> 5. The order in which tapes are run is not clearly described. In fact,
>> the relevant section is utterly incomprehensible. Surely *they* know
>> what they meant - but *I* haven't got a clue!
>> 
>> 
> Ask for clarification.

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

Jim

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