tony writes: Actually, it's even a bit funkier than that. I spent a lot of time messing around with the tape drives that same with Sun-2's (QIC-11) and Sun-3's (QIC-24). SunOS on a Sun-3 had two devices for each tape drive, which determined whether it used QIC-11 or QIC-24, and for reading it was smart enough to autodetect and use the correct format regardless of which device you used. So far so good. I started out with Sun-3's, and for a while I didn't think there was actually any difference between the two devices, since I could get approximately the same capacity (~60M) on the tape using either one, whereas QIC-11 is supposed to only be 20M. When I got into Sun-2's, I discovered that there was a difference, and I had to use the correct device on a -3 when prepping a tape for use on a -2. In addition, I had to be very careful not to overrun the 20M limit, because the drives in the -2's would only read 20M, per the spec. As long as I wrote less than 20M, in QIC-11 format, the tapes would work fine, but I had to enforce the 20M limit manually. It took some investigation to discover that the QIC-11 standard was at some point extended from four tracks to nine tracks, and obviously the QIC-24 drives used in the -3's supported the extended standard. I wish SunOS had included a third device to allow distinguishing between four-track and nine-track QIC-11, but perhaps the drive or the drive/SCSI bridge didn't provide the necessary pseudo-EOT notification. --James B.