NBU Tapes Kbytes

[Puffy]

Hi,

I am checking how many tapes I required for a particular job. One odd thing I note is that a backup job from Activity log may say 600GB of data backed up. But only 1 tape is used.

However we only have LTO3 tape (400/800GB).

I check the tape capacity using bpmedialist. I was thinking whether the tape capacity is based on data compressed (removing white spaces etc), or the raw data.

Thanks a million.

NBU 6.0 Windows 

[scored_well2]

Puffy,

The amount of data you can fit on a tape is entirely down to the data you're putting on there, and the compression ratio you can get from that. 600GB for an LTO3 seems fairly standard to me - 1.5x uncompressed capacity. Some people claim to see many multiples (e.g. 5x which would equate to 2,000GB on LTO3) if using easily compressed data. You will see more data stored to a single tape if it comes from a database, e.g. SQL or Exchange, and far less if the data is already in a compressed format, e.g. .zip or .jpg files.