[lopsa-discuss] tape drive recommendations

[Scott Francis]

On 12/9/05, Bruce A. Hamilton <bhami at pobox.com> wrote:
> At 10:58 PM 12/8/2005, Scott Francis wrote:
> >... 35GB of data... to back up daily, ... 2x their current needs
> >should last them at least five years).
> >
> >...small business client with limited funds, ...
> >... between 50 and 100GB of data
> >(uncompressed) ... I expect to spend
> >$500-$600 on a suitable drive, but I'd like to keep the cost of
> >cartridges down under $20 each if I can.
>
> It sounds like you're pretty much limited to DAT72, based on your
> budget. I'd be interested in hearing what sort of compression folks
> get with that. On my DDS4 drive (the generation previous to DAT72) at
> home I only get 25 GB per 20 GB (uncompressed) tape (Windows XP,
> typical mix of email and whatnot).

I'm seeing AIT-1 and AIT-2 50/100GB drives in that same price range
via pricewatch.com (granted, what you see isn't always what's
available in the end). Assuming equal levels of support by the OS for
the various hardware formats, are there inherent
advantages/disadvantages to AIT vs DAT vs SDLT (I already know your
opinion on the earlier LTO formats :)) ?

> Everything has been wonderful since we converted to LTO2 about eight
> months ago. We ran many of the LTO2 drives with LTO1 media for quite
> a few months and saw slight improvements in throughput and error
> rates, but only with LTO2 media do we get consistently clean backups.

That more or less confirms my own (rather limited) experience with
LTO2 from a few years ago. I'll keep this in mind the next time
enterprise-level backup becomes an issue.

I also had someone reply off-list asking whether I'd considered
external hard drives as an option - they are getting very affordable
(at $500-$600 for a tape drive plus cost of media, I could just about
break even with 7 80GB IDE disks and a USB/firewire enclosure).  My
concerns with using HDD for backup have traditionally been the
relatively short lifespan (as compared to tape) and the ability to
achieve the "snapshot in time" that a true backup affords (versus
merely mirroring whatever the current production data set is). If
$user deletes a file on Monday, the deletion is archived that night,
and the user decides on Thursday she'd like the file back, I'm out of
luck if I'm merely mirroring the production data to an external disk
every night. I'd need (say) 5 external hard disks, each labeled for a
day of the week (M-F) to get the same effect as a nightly tape backup.

But I suppose that's more of a policy matter than an inherent
disadvantage of using disk for backup rather than tape.

One last question - software. I'm quite comfortable with the assorted
options available in a UNIX-like environment, but when Windows comes
into the mix, I'm a little less clear. I'd like to avoid any (usually
expensive) commercial backup software if possible, and either use a
native backup functionality in Windows (server 2003), if such exists,
or else use a *nix server to back up the Windows data (Samba-mount the
Windows data on the *nix side, or perhaps cygwin+ssh+rsync on the
Windows server to the *nix server, where it could be backed up like
anything else). Any opinions on these (or other) options, one way or
the other? I'm not too concerned with backing up registries or other
Windows-specific data - primarily just applications and user data. The
OS can always be reinstalled in case of any problems, and I'm going to
have the user account information mirrored on a Samba server.

cheers,
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