Hello, Four years ago I deployed a pair of Tandberg LTO-5 Ultrium (SAS) tape, connected a Dell PowerEdge server via a Dell H200 SAS controller.
At that time ran the amtapetype utility which produced this output:
define tapetype Tandberg-LTO5 {
comment "Tandberg LTO5 1500/3000, produced by tapetype prog (hardware
compression off)"
length 1410 gbytes
filemark 0 kbytes
speed 125762 kps
}
(That was created by an older version of AMANDA, which we were using at
the time: probably from Debian/Lenny, which was version 2.5.2p1, I
believe)
These tapes are native 1.5TB and so that looks pretty reasonable. We've
never used these tapes to their fullest capacity and all was fun and
shiny until recently when the tapes reported "No space left on device".
However, the concerning thing is that the tapes reported 'full' at less
than what I was expecting as full capacity, just above 1.1TB in fact.
This means that our backup space 'growth', which I had been assuming was
only 75%/80% full is in fact at 100%!
I re-ran the tapetype utility from our current AMANDA (version 2.6.1p2-3
from Debian/Squeeze) and it showed this:
define tapetype unknown-tapetype {
comment "Created by amtapetype; compression disabled"
length 1148746080 kbytes
filemark 0 kbytes
speed 69815 kps
blocksize 32 kbytes
}
The length reported here is ~1.1TB which ties up with the "no space left
on device" message, but ...
... these are genuine LTO-5 (Tandberg brand) tapes - just like
http://img.misco.eu/Resources/images/Modules/InformationBlocks/1210/TAN/TAN-2/202175-tandberg-LTO-5-tape-cartridge-small.jpg
- and the second tapetype above was created using a previously-unused
tape and they really are 1.5TB native!
What's going on? Why am I not getting to use the full capacity??
Cheers,
Dave.
--
Dave Ewart
da...@ceu.ox.ac.uk
Computing Manager, Cancer Epidemiology Unit
University of Oxford
N 51.7516, W 1.2152
signature.asc
Description: Digital signature
