backup advice sought

[Alan Jackson]

On Sun, 7 Mar 2004 08:38:47 -0500
dep <dep at linuxandmain.com> wrote:

> morning, gang!
> 
> and i don't know where to begin. ideally, i'd back up daily to another 
> drive with an independent power supply -- or something like that. if 
> there are tape drives or similar that are not insanely expensive and 
> that have a decent capacity, that would be good to know. i do not want 
> to spend a thousand bucks here, but i also would be well and truly 
> screwed -- i mean lawyer-grade screwed -- if i lost my stuff.
> 

I have done disaster planning years ago - it's tricky to get it right.

First step is to figure out what you are trying to protect against.
For example :

- Fire/flood/tornado/... backups are for full system restore after a
  major catastrophe, and must be kept offsite. That sort of eliminates the disk
  mirror gambit, but it also says that maybe monthly is sufficient. Probably
  looking at tape.  At work we have generally gone as cheap as we can and still
  get the performance necessary to be able to do a full backup over a weekend.
  For example, 8mm is not too pricey, but it is slow. If there is too much data
  such that you can't physically put it onto 8mm in 2 days, then more expensive
  tapes, what are they, can't remember. The high capacity cartridge things.

- User stupidity (oops! I didn't mean to delete that!) ... backups are for
  single file recovery. Incremental tars onto a mirror drive work well
  here. 

- hardware failure - I'd seriously think about a server with Raid-5. We
  bought like 1/2 a Terabyte of raid-5 in a small box for $5k a year or
  so ago. Hot spares and the whole thing. What a deal!

One could (and maybe should) do all three. Each problem has different 
requirements.

At home I do incremental tars onto another drive, and burn a CD periodically
that I take to work (off site storage!).

Other things to consider - are there files (especially large ones) that are
not really critical? The smaller you can make the backups, the easier it
all becomes. Small enough and you can use DVD's.

-- 
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| Alan K. Jackson            | To see a World in a Grain of Sand      |
| alan at ajackson.org          | And a Heaven in a Wild Flower,         |
| www.ajackson.org           | Hold Infinity in the palm of your hand |
| Houston, Texas             | And Eternity in an hour. - Blake       |
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