terry schreef:

I followed this howto here
http://www.howtoforge.com/disk_based_backups_amanda_debian_etch
and of course adjusted for my os but when I run a backup I get an email
containing

These dumps were to tape DailySet1-2.
The next tape Amanda expects to use is: DailySet1-3.

FAILURE AND STRANGE DUMP SUMMARY:
  bigfish.bluelight.org.uk  /  lev 0  FAILED [disk /, all estimate failed]

[...]

any pointers welcomes

Just pointers:

a more complete setup for the beginners:
  http://wiki.zmanda.com/index.php/User_documentation

Frequent problems and their solution:
  http://wiki.zmanda.com/index.php/Troubleshooting

To be able to help you, you have to give more information
and especially the error messages found in the debug files
that amanda generates for each run.

One of the first things to try is running amcheck and
solve every problem it encounters.
Did you run amcheck without errors/warnings?