Is it possible to backup large disk?

I ask because I want to backup a disk with 300 GB to DLT1 or LTO1.

The DLT1 is a backup library with 7 slots which works fine.
The LTO1 is a sigle drive. I tried it as single drive an as
chg-manual.

I configured a holding disk with 12GB (I don't have more).

Amdump always sends me this error:

FAILURE AND STRANGE DUMP SUMMARY:
  sun.moonsm /export lev 0 FAILED [dump larger than tape, 160459105
KB, but cannot incremental dump new disk]

Where is the problem?


Thanks
Thomas