DEC TZ89 Drives (DLT7K) Out of a Compaq ESL Library not Compressing on HPUX11i

[Alzhy]

Trying to setup DEC TZ89 (DLT7000) drives out of a Compaq ESL9000 series library on an N-Class running HPUX11i. Installed the latest stape patches(PHKL_29248).Using the default ATT/BSD device entries(ie. /dev/rmt/99m or /dev/rmt/cntndnBESTnb).. I could only save 35GB to DLTIV (35/70GB) media even if my data are highly compressible. I tried manually creating a device entry using mksf and the appropriate mtio.h density to force compression but could not get it to compress. I tried the following:

1. mksf -d stape -H 1/2/0/0.81.4.255.0.0.7 -b 133 -u -n -c 1 /dev/rmt/dlt7drv5
creates the device and lssf shows an "mt stat" on a tape shows 70GB compressed BUT, I could not write to tape

2. mksf -d stape -H 1/2/0/0.81.4.255.0.0.7 -b DLT_85937_52 -u -n -c 1 /dev/rmt/dlt7drv5
creates the device file, lssf shows compressed with the density of DLT7000 but "mt stat" shows it as 35GB capacity AND I can write to it-- however up to 35GB of data only even if the files are highly compressible.

Anyone out there using the same DEC TZ89 DLT drives and was successful in doing compression?

Thanks!

[Peter Marais]

Tested your command in 1 above and it worked fine for me. Check your media that it is IV and not III.

Regards