Re: Tape/DVD Backup Suggestions?

On Thu, 18 Jul 2002, Kurt Gunderson wrote:
> You might try looking into DLT technology.  DLT tape drives will give
> you 80Gb storage with ~6-12MB/s throughput.  They are an industry
> standard supported by the heavyweights (HP/IBM/Dell) but a little more
> pricey than your current DDS technology.
>
> If you are looking for speed AND storage, I would suggest a combination
> of disk and tape.  Back you 'production' data to a separate 'backup'
> drive then write the 'backup' drive contents to tape.
>
> If you have money to burn and require very little downtime during
> backup, place your data on a mirrored disk.  During backup time split
> the mirror and backup the stale mirror to tape.  Once you are done,
> re-sync the stale mirror to your production mirror (which can be done
> online).
>
> Tony Reina wrote:
>
>  > I'm looking into new ways of backing up the data in our lab, including
>  > the PostgreSQL database. Currently, we have a single DDS-2 tape drive
>  > capable of holding 8Gig compressed. However, it is slow (i.e. takes a
>  > day to backup about 40 Gig of information), spans multiple tapes, and
>  > makes it hard to find just a single file or two on the backup (i.e. I
>  > have to go through many tapes before I can find and extract one of two
>  > files).  Our CDRW backups are easier to manage and relatively fast,
>  > but require dozens of CDRWs.
>  >
>  > Can anyone make suggestions on backup systems? I was thinking that
>  > some sort of DVD writing system would be good for accessing one or two
>  > files in the backup quickly.  It would probably also complete backups
>  > faster. However, I think DVD's only hold a few Gigs on them. Are there
>  > systems like with these features that could handle say 20 Gigs per
>  > media?

Weigh your needs vs. technology available first. If you need speed and
large capacity and want to use classic backup media (ie: sequential), look
no further than some of the high end tape drives. DLT is at the lower end
of "high end", but it will still work OK. There's also LTO, STK, IBM
3590... You can spend as much as you want to spend. If speed is your goal
beyond anything else, get IBM 3590 (others may be as fast, but I know this
drive is pretty advanced as far as features). If you want
price/performance, get DLT.

I don't really see any of the consumer available optical devices (ie
DVD-RW or CD anything) as viable backup devices unless your data will fit
on them and speed is no concern. They are slow and rather small compared
to almost any modern tape drive. DDS may be excepted, I think those are
pretty slow but I haven't looked into them lately.

Based on what the last post said, you may want to go with a backup program
like Amanda which will make tapes for you after first staging the data in
a disk holding area. This works at the filesystem level though, so you'd
have to have your database data consolidated carefully.

Andy

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