enable compression. ULTRIUM 920

[yojarmye]

I have an Ultrium 920 (400/800 GB) installed and running on a redhat linux.
I want to enable hardware compression to copy up to 800 GB of information.
Looking for information I've found that setting:
# mt-f / dev/st0 compression
worked, but it is not, when it comes to 400 GB of info does not copy over.

Any idea how?

Thanks.

[Marino Meloni_1]

usually compression is enabled by default on LTO drives
And the backup application is the one that may turn compression on or off during the backup.
May be you can check if that exist in your backup application or the backup command you want to use

[yojarmye]

thanks for the reply.
I use to copy to tape a script:

tar - label = "BACKUP $ DATE_INICIO" - verbose - create - absolute-names - blocking-factor = 128 - file = / dev/st0 - files-from "$ LIST">> $ LOG

Then, the compression hardware should enable it from the "tar"?, as would do this?

[Marino Meloni_1]

ah ok, I understand you are not using any high level backup application but native Linux commands.

Usually the backup aplication can set a flag to change the compression mode using a scsi-3 mode page 0x0F command.

unfortunately I'm not a Linux guru and do not know the CLI command for that.