DDS3 cant hold enough data?????

[nath01]

I have an nt4 server that is used as a file server.

I am trying to backup the whole of d drive to a DDS3 tape, however it always stops half way through and wants another tape! Even though there is only 18gb of data getting backed up!

using ntbackup I have compression set up correctly but why wont it take that amount of data on a tape?

 

[Jesperrim]

The DDS-3 format supports 12GB native and 24GB compressed capacities. The 24GB is no guarantee though! If you try sticking 10GB of already compressed data on a tape you might end up with 11 or 12GB actual data, as the pre-compressed data can 'grow' when subject to an attempt to compress it over again.

You need to verify what type on compression you are using, Hardware OR software - Not both! I work by a rule of thump; Whoever supplies the drivers for the drive, supplies the compression!

Have a look in the log files for soft-write errors. The indicate that your drive is wasting precious tape by rewriting data. If large amounts of soft-write errors, clean the drive and run chkdsk on the backup source drive.

If this still doesn't help - update every driver and firmware the data meets on its way to the tape drive!