ADIC has some pretty high-end libraries.  Their AML/2 library claims a top
capacity of over 5PB, 400 drives, and over 7,600 pieces of media.  It
supports around 20 different media types.  When SAIT comes out, that
capacity would likely go up significantly higher.

At 05:51 PM 11/19/2002 +0000, Dan Foster wrote:

Hot Diggety! Orville Lantto was rumored to have written:
> A 72 drive, 10 I/O slot 3584 library will hold 2207 cartridges.  with 175
> GB/cartridge that works out to 6 libraries.

Aye, in terms of tape capacity. However, if you have a requirement that
it finish an entire full backup in a single day -- say, 20 hours...and
you get between 15-30 MB/sec for HW compressed writes with the LTO drives.

So we pick a common number that's actually sustainable in real life: 22.5
MB/sec.

22.5 MB/sec * 72,000 seconds (20 hrs) * 72 drives * 6 libraries =

683,438 TB, or about 32.6% of 2 PB. Therefore you need 3 times the
original number of 6 libraries, and that's assuming you can keep up
this rate constantly for every single second of 20 hours.

18 fully decked out 3584 libraries would be something to behold, I think ;)
That'd span 106 frames and 1,296 LTO drives. A single full backup would
run about $18M (list price) worth of tapes in that kind of configuration.
I'd like to work for a place that can afford it! Even after deep
discounting, that's still $8-10M worth of tapes.

-Dan

--
Paul Zarnowski                         Ph: 607-255-4757
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