Subject: HD as backup (Re: RAID In general)
To: None <>
From: Chuck Yerkes <>
List: current-users
Date: 04/17/2003 14:41:52
Quoting Greywolf (
> Thus spake Wojciech Puchar ("WP> ") sometime Today...
> (me)> ...much about speed and data size omitted...
> WP> but not with DAT media or CD-RW
> You obviously missed the speed/size thing.
> Several points:
> * DDS-4 drives still run a hefty chunk of change, and DDS-4 media aren't
>   that cheap.  And the drives are still slow.  Last I checked, drives were
>   $500 or more, and media is $25 each, and you get 20GB on a tape.
>   Initial cost to back up 100GB: $625 plus applicable taxes.  Subsequent
>   cost to back up 100GB: $125 + applicable taxes.  Speed: slow.  Setup
>   considerations: low.

After giving lockbox full of backup media to an offsite storage sites
driver (who's main technical skills involve, er, driving):
Confidence in tape media when driver drops the lock box at the elevator?

> * CD-RW is slow, and you still only get 800MB/CD.  Does anyone out there
>   have the courage to run 'dump 0usdf 16000 64000 - / | cdrecord [args]'
>   and not worry about creating a coaster?  Or would one have to pre-split
>   the backups into 800MB chunks and iso them before cd-recording them?

like amanda does for me?

>   This would defeat the purpose entirely.  Cost for a burner: $60.
or $30.  And this gets spread per use.

>   100GB/0.8GB = 125 CD-RW.  Price per CD-RW: $1.  Initial cost: $185 + tax.
or readonly disks at around $0.10 each (10 of these equals one CD-RW).

>   Subsequent cost: $125 + tax.  Speed on writing: slow.  Speed on reading:
>   Acceptable.  Setup considerations: high.

> * HD might run a little more.  I've seen 100GB drives for $125 on sale,
>   maybe $150 otherwise.  (IDE, obviously, since that's what we're discussing).
>   Initial cost: $150 + tax.  Subsequent cost: $150 + tax, probably less
>   as HD prices go down.  Speed on reading and writing: fast.  Setup
>   considerations: low.
Number of copies?  1.

> This all misses the point that hot-swappable IDE would STILL be really nice
> to have, for a variety of reasons.

I find your use of "initial" and "subsequent" to approach the genuineness
of marketing folks.  It's there because it helps your harddrive option only.
Your wording encourages people to give equal weight to acquisition costs
and costs of use.  In FACT, the acquisition costs should be spread over
life of the product.
The cost of CDdrive/Tape acquisition can be spread (for taxes) over 3 years.
It should be spread (business argument) over the life of its use.
HD's ONLY have initial costs.

I have an DDS 4 that's 4 years old and has made over 300 tapes (in not-heavy
Let's account for that cost ($600) to $2/tape.  Now my 20GB tape costs
are $27.  And I reuse tapes.

I have a DAT that I mail to a pal cross country every couple months.
I'd never do that with an HD.

I have a DAT sitting on my desk.
I can't safely do that with an HD.

I have a box of tapes (8mm, QIC150, DAT from DDS-1 to DDS4) sitting
in a box in a closet.  They all still work (I question the 9-track's
life after 18 years since backup).

I also have a 20MB MFM (or RLL) drive that's got some stuff I might
want.  Could you run over and get that data off please?

- HD's are delicate.
- Tapes survive more external extremes.  Tapes are a consumable,
  they duplicate for low costs, etc.
- Tapes survive TIME far better.
- Tape media, in my experience, are still usable after 10+ years.
  Even in my environmentally icky home use (I've carried 8mm through
  hot summers in closets).  Locked in a machine room, they do better.
  I can find QIC, 8mm, DAT, Syquest, Zip/Jazz and even 9 track and
  Punch Card readers with interfaces I can attach to current computers.

I expect 25-30GB DVD writers within a year or two.

Yes, I backup stuff to a large HD in a different server.  Yes,
I have tape backups.  I know that in 5 years, I will still
have those tape backups and that I will still be able to use them.

"ooops" a static bump just zapped that hard drive.  Hope it wasn't