>The tape device I am using is 0lbn. We are using software compression >on the dumps.
That's probably not the right device name to get 35 GBytes on a DLT-IV tape with a DLT7000 drive. You should be using 0hn (drop the 'b' -- it will lead you down a dark path). Assuming you have not messed with /kernel/drv/st.conf, the default settings for a DLT7000 are in "DLT7k-data": DLT7k-data = 1,0x38,0,0x1D639,4,0x82,0x83,0x84,0x85,2; The last four hex values (0x82,0x83,0x84,0x85) specify the density code sent to the drive when you use (respectively) 'l', 'm', 'h' and 'u' (or 'c') in the device name. Looking at a DLT7000 manual, 0x84 sets the drive to 35 GBytes, no compression, so you want the 'h' name. >... "significant" was around 40 gigs, ie around 20 compressed. You're actually getting 2:1 compression? That's a borderline miracle :-). >Our last short dump line: > taper: tape VOL2 kb 19915968 fm 99 writing file: short write This matches perfectly with above. You got 20 GBytes on a tape, which is what the 'l' density code (0x82) told the drive to do. >The device name we use is /dev/nrst1. ... I'm confused. I thought you said you used 0lbn? In any case, I recommend you change it to "/dev/rmt/0hn". It's not 100% clear whether DLT7000 drives (possibly in conjunction with the Solaris st driver) will properly switch to a new density just by using the different name. They *should*, since the tape is rewritten from BOT, but I seem to recall having some trouble. Try just changing the device name, then look at the "taper" line in your next report. If it shows more than 20 GBytes written, you're all set. If it does not, you're going to have to force the issue on each mount via the front panel until all the tapes get rewritten once (sigh). >As for the tape mounting at 35.0 gig >density, I did not consider any change in it since Amanda was mounting >the tape (again, the tricky word assume creeps in) Amanda may have mounted the tape, but you're the one who told it how to do it :-). >Michael Campfield John R. Jackson, Technical Software Specialist, [EMAIL PROTECTED]
