wojtek@wojtek.from.pl writes:

>1) how to turn off tapesize calculation. i have DDS-2 drive with
>compression but dump prompts for next tape after few minutes

specify a (conservatively estimated) value of tape capacity in kilobytes
with -B.
And no, I don't think it's a good idea using the drive's compression
mechanism for _backups_...

2) how to dump all filesystems mentioned in fstab with nonzero dump flag?

well, basically you dump one after the other :)
use /dev/nrst0 (the non-rewind-on-close device) if you want to keep
more than one dump per tape, and use mt for positioning.

mkb