Subject: Re: DLT drives
To: Ken Hornstein <kenh@cmf.nrl.navy.mil>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: current-users
Date: 02/25/1999 10:17:22
On Feb 24, Ken Hornstein wrote
> Anyone use a DLT tape drive with NetBSD?  If so, did/does it work well?
> 

Just setup a backup server on a NetBSD 1.3.3 machine:
ncr1 at pci0 dev 11 function 0: ncr 53c810a fast10 scsi
ncr1: interrupting at irq 10
ncr1: minsync=25, maxsync=206, maxoffs=8, 16 dwords burst, normal dma fifo
ncr1: single-ended, open drain IRQ driver
ncr1: restart (scsi reset).
scsibus1 at ncr1: 8 targets
st0 at scsibus1 targ 4 lun 0: <QUANTUM, DLT7000, 204B> SCSI2 1/sequential remova
ble
st0: st0(ncr1:4:0): 10.0 MB/s (100 ns, offset 8)
density code 0x1b, variable blocks, write-enabled
ch0 at scsibus1 targ 6 lun 0: <OVERLAND, LXB, 0331> SCSI2 8/changer removable
ch0(ncr1:6:0): 10.0 MB/s (100 ns, offset 8)
ch0: 14 slots, 1 drive, 1 picker, 0 portals

(ch0 has 15 slots, but I reserved one for the cleaning cartrige).
Software is the amanda 2.4.1p1 package I commited 2 days ago.
I didn't notice any problems yet, lthouh I didn't use it extensively.
I'm still moving clients from the Sun/Hexabyte to the NetBSD/DLT,
so it's at 20% of the tape capacity for now.

> While I'm on the subject ... anyone got any reasons to love/hate DLT
> tape drives versus any other type of tape media?
> 

I've got lots of problem with hexabytes (can't read back tapes written
too long ago, or with another drive, but this seem very dependant on the
quality of the media: original hexatapes seems much better, but also much more
expensive :). I also used DATs, I've been hit by incompatibilites between
drives too. In both case, medias don't survive a few dozen of write cycles.
A fried of mine bougth 2 DAT changers, he never has been able to do real work
with them.
I had to set up a DLT library 3 years ago, and managed it for a year.
I never got any problems with it, and found it really fast. I've also
got good reports from other peoples I know. The tapes are expensive but
seems to survive a lot of write cycle, the capacity is also higther ...

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
--