Subject: Re: Conner minicartridge tape drive - quirky drive
To: Stephen Brown <sbrown@best.com>
From: John F. Woods <jfw@jfwhome.funhouse.com>
List: current-users
Date: 07/20/1999 16:51:26
> > > on boot as a "Conner CTMS 3200 7.15".  It takes QIC3080
> > > tapes and supposedly is capable of storing 2GB 
> > > (uncompressed) on each tape.

I've had both the CTMS-3200 and the successor CTMS-8000 (which holds 4G on
TR-4 Travan cartridges), and they both work perfectly well on x86-based
NetBSD.  The only quirk I noted was that the drive is limited to logical block
sizes of something like 24KB per block; the early CTMS-3200 drive I had would
lock up solid trying to read a tape written with a blocksize larger than that.

(The tape format has a 512-byte physical block size, but layers a logical
blocking scheme on top of that; the drive manual courteously sent to me by
a Conner engineer didn't explicitly document any logical block size limit,
but the description of the tape format (several blocks of data followed by
a few CRC blocks) gave me the hint to try using "tar" with reasonable
blocksizes (rather than "tar cbf 100 ..." which I used to be in the habit
of doing for backups (because it was faster on the hardware I used to use)).)