[geeks] Well, THAT was a setback

[der Mouse]

>> It is, however, a good point that if the drive streams 40MB/sec, you
>> need more than 100Mb/sec incoming bandwidth to keep it busy.  Four
>> 100Mb interfaces might do, if they're shared in sufficiently clever
>> ways, but unless there's some reason to avoid a gigabit-capable
>> switch, you'd probably be better off with gigabit.
> Yup.  Only budget for the switch and NICs is keeping me from it.

I think that counts as a reason.

But 100Mb switches are cheap and plentiful.  So are 100Mb cards.
Perhaps four (or five or six) 100Mb cards would do?  Figuring out how
to spread the load could be interesting, but even if you can't quite
hit that 40MB figure, you might come close enough to improve things.

> It's the monthly full backups that are the problem,

Hmm.  Is there any particular reason you have to do all the fulls at
the same time?  Do your fulls have to be done at a particular date, or
do you just have to get a full done each month or so?  If the latter,
Amanda might be worth looking at; that kind of load-balancing is one of
its strengths - give it a few months and it's pretty good at spreading
things out so each run generates about the same amount of data.  (To
the extent possible; if, for example, you have two big disks and
nothing else of significance, it'll do the best it can but it won't be
able to even things out much.)

> because until I can spare the money for a complete set of new disks
> for the server, I only have enough disk space free on it to have a
> single full backup to disk in existence at any one time.

You can't just pop in a SATA card and plunk one of those 931G drives on
it?  That would give you well over one full tape's worth of buffer
space for maybe $150 - and it sounds as though that would be more than
offset by human time saved, though I'm aware it's not always feasible
to trade off staff time versus hardware budget.  (It's not clear to me
who's holding the purse strings in this case.)

> [I]t ended up taking about twenty hours to write five LTO-1 tapes,
> with tape changes every four to five hours.  *That's* the part of the
> whole operation I'd like to speed up enough to at least fit into the
> waking hours of a single day.

I don't entirely understand the explanation about why you couldn't dump
to disk and then write it to tape later, but I suspect that's because
Bacula concepts I don't know are involved (I have a general knowledge
of what Bacula is, but I've never worked with it and thus don't know
details).

Is there some reason it has to be done entirely within Bacula, though?
Maybe tell Bacula to dump to disk and then handle moving things between
disk and tape with other tools, so Bacula always deals with disks?
Seems to me that might make the migration-between-hosts issue you were
talking about irrelevant, if it would work.

Or maybe sneakernet the buffer disk?  Once a month might be feasible.

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