Re: IDE DAT Drive?
> From: "Russell Coker" <russell@coker.com.au>
> To: "Peter Billson" <pete@elbnet.com>; <debian-isp@lists.debian.org>
> Sent: Wednesday, November 22, 2000 3:03 PM
> Subject: Re: IDE DAT Drive?
>
> On 2000-11-22 11:44, Peter Billson wrote:
> >Can anyone offer any info about IDE DAT Backup tape drives for use under
> >Debian? The How-tos all talk about floppy drives and I am not sure if
> >some/all/none of these drives are supported.
>
> DAT isn't what I would choose to use for backups. DAT isn't known for
> long-term reliability.
Backup is about cost effective medium term storage. Long term storage is
tricky, are you really
sure anyone will be bothering with CD-ROM format in 30 years time? What
about DVD? Can you even remember what peopler were using 30 years ago? I
have over 300GB of storage to backup,
I'm wondering how many weeks it would take just to perform one full backup
to CD-ROM,
no thank you!
Tape still has lowest cost per gigabyte. Earlier this year the Onstream IDE
drives with 30GB
capacity were the most cost effective, and having used ADR-50's from
Onstream, they appear to
be much more robust than DAT or DDT technology. Time will tell, the
mechanisisms are simpler
so there should be a lower MTBF. The IDE versions are supported by the
kernel since 2.2.16,
patches were available before then, and tend to be faster and more robust
than DAT technology
which is based on consumer audio recording. Consumer grade components are
cheap, but tend to
fail.
If you have to keep tape long term, you need to retension them, store them
properly, and you should
expect to have to copy the data to a more modern format as you migrate to
newer technologies.
This is only worth while for very important data, may be you have to hold it
for legal reasons.
> I use CD-R for long-term backups and archives copied to the hard drives of
> other machines for short-term backups. CD-R should survive for decades,
> there is no chance of accidentally over-writing it, and 650M of bzip2
> compressed data is more than enough for most backups!
Very useful for archives of material which is being removed from a system,
if it fits.
> For short-term backups (when you accidentally delete yesterday's files)
then
> an archive on the hard drive of another machine is most conveniant. Even
an
> archive on another hard drive of the same machine is quite good (it'll
take
> something quite serious to destroy two hard drives at the same time).
A disk staging area is a great benefit. It certainly is very convenient to
be able to rescue,
new copies of files, without unlocking the tape store.
> Oh, don't backup user's mail directories. They change so much that a
backup
> that's more than 1 day old is probably useless.
This may upset users when they loose days worth of email, that they were
unable to download,
or had left on the server, because they were travelling.
Sorry Matt, I don't know the answer about IDE DAT drives, unless you need
DAT tape compatability
I'd use the Onstream IDE 30GB for lowest cost. Otherwise, a reasonable SCSI
card and drive would
not be a bad investment, if you're worried about compatability.
Rob
Reply to: