Using ACSLS drives - Tapes writing more then capacity - all LTO3 tapes show morethen 2 TB

[Tekkali]

Any please suggest all LTO3 tapes shows more then capacity. Acsls tape drives SL500 Library. in solaris.

Netbackup verison ;7.5.0.4

Thanks

[RamNagalla]

no worries.. this is normal... this is because.. tape drive do compression before wirting the data to the tapes... so based on the data type you can have the more compression and write more data into the tape..

and netbackup shows the data size before the compression..

amount of data that you can write on the tapes depends on the compression ratio, you can see normal data files have more comperssion and they do write more data on single tape and reach full status

where as database files or media files have less compression and write little be less data on single tape and reach Full status.

looks you have the good compression ratio for the data that you are writing to tape that is the reason it is showing more data size..

[RiaanBadenhorst]

You should be celebrating :)

[Andy_Welburn]

\o/

From some time ago with a nice solution & a couple of further 'informative' links:

https://www-secure.symantec.com/connect/forums/media-list-question

[Tekkali]

Hi All

Thanks for info :)

It's hardware comperestion. why we are not used policy compresion ?

Can I use both ? wt is the difference ? which is recomanded ?

Please suggest...

[Marianne · Accepted solution]

Policy compression is only recommended for clients on slow network.

Policy compression puts a lot of overhead on the client (memory).

Hardware compression is recommended. As you can see, you are getting excellent results. Leave everything the way it is.

[Tekkali]

Thanks Marianne.