LTO8 and LTO6 cartridges not writing compressed data

  • 16 August 2023
  • 3 replies

Userlevel 3
Badge +10

Hello, Team

I have a customer who is writing directly to the tape library with any dedupe in place. Their challenge is, for their LTO8 and LTO6, the data writing to tape is making use of the native capacity instead of the compressed capacity. 


They have the hardware compression enabled on each of their storage policy and they confirmed that before moving to commvault, their previous backup solution makes use of the compressed capacity when writing data.


Is there any settings that can be done on commvault to ensure that the data is compressed so it can write full capacity of the data?

Please, advise

3 replies

Userlevel 3
Badge +6

Hello @Mubaraq,


Commvault does software compression and sends compressed data to the tape drive. hardware compressions is useless in such scenarios and you will not get any compression from the tape drives in such scenarios.




Userlevel 7
Badge +19

As Mike said you should calculate capacity for tape media based on native capacity. 

Userlevel 4
Badge +10

Hi @Mubaraq 

Hardware compression is performed by the tape drive, you will need to reach out to the HW vendor of the tape drive to find out why it’s not compressing the data.

Let me know if you have any questions. Thanks