Incremental/differential

[dmauri]

Hi list,

((Arcserve v9.0 build 2200, W2k server SP4)).

We use a Hp ultrium tape 8.
The lto cartridges are 200gb capacity.
Each day we make a full backup, but I would like to reduce the gb for daily jobs because I get errors about the capacity. So, I'm thinking about to change the way I have the backup. Should I make a differential or Incremental daily jobs? then in the weekend make a full backup?
Is this a correct way to do the backup?
What is the main difference between differential and incremental?

Thanks

 

[ntinlin]

Differential

Backs up all differences between one full backup and another - does not reset archive bit

When doing a full restore you would need the full backup tape and the latest differential

Incremental

Backs up all differences between previous backup and this one - resets archive bit

When doing a full restore you would need the full backup tape plus every incremental tape since that backup


Incremental
Pros - Tend to be quicker backups since only doing one days worth of changes (usually)
Cons - All incremental tapes need to be applied during a restore so you'll be changing tapes a lot

Differential
Pros - Quicker to restore since usually no tape swapping (depending on capacity)
Cons - Slower than incremental since it will be backing up more data in the main

Personally I always try and go with differential if I'm sure that all the changes between one backup and the next will fit on one tape

Neill