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DDS4 problem

Lee Tae-kyung
Regular Advisor

DDS4 problem

Hi everyone...
HPUX: 10.20
Tape: DDS4
Problem : I want to backup 40G Data, but DDS4 is backup only 20G data with tar or fbackup command.
Please help me...
I think I am a specialist in IT Korea^^. I am a programmer and SE and DBA
Michael Tully
Honored Contributor

Re: DDS4 problem

Using a 150M tape will get you 20Gb Raw,
but up to 40Gb with a full compression
ratio, which is highly unlikely. A DLT
drive will serve you much better in the
way of capacity. There are various backup
tools that will ask for a second tape in
HPUX. fbackup is one of these.

Anyone for a Mutiny ?
Alexander M. Ermes
Honored Contributor

Re: DDS4 problem

Hi there.
As Michael has mentioned, try a DLT.
Check for Quantum or StorageTek.
Perhaps you can get one for test purposes.
Alexander M. Ermes
.. and all these memories are going to vanish like tears in the rain! final words from Rutger Hauer in "Blade Runner"
Vincent Farrugia
Honored Contributor

Re: DDS4 problem


A DDS4 tape holds up to 20Gb of data in raw format. It is stated that it holds 40Gb of data since it is assumed a 2:1 compression rate. In theory, it can hold a lot more data than that, since some data is compressed at a greater ratio than 2:1. It just depends on the data you want to store. If the data is already compressed, then it will hold only 20Gb of data. If data is text, then you will probably be able to store more than 40Gb.

A DLT tape, however, stores up to 40Gb raw data, and up to 80Gb if we assume a 2:1 compression rate. So it should work for your purposes.

Follow these links for more information:


Tape Drives RULE!!!