Enabling Compression on Ultrium LTO-2 Tape Drive
 

We have been using an Ultrium LTO-2 tape drive to perform backups of certain information from our file server. Recently, the data that we are backing up has grown too large to fit on the tapes in their 200GB uncompressed capacity. I have been looking around for a way to enable the compression in the drive, but I haven't found much. I am not using any backup software, so I'm not sure if I'll even be able to. I write the tape using a simple 'tar' command, so there aren't a whole lot of options to be set. Is there a way that I can enable the drive's compression, or would I be better off running the tar command with the gzip or bzip flags?

Hi,

hardware compression has to be enabled by the hardware. Best take a look if there are any DIP switches on the tape drive where you can enable this option. The hardware vendor of the drive should provide the manual for the drive to determine the correct switch settings.

I have contacted the vendor I got the drive from. Unfortunately, there is no physical switch to change the compression settings. It was recommended that I use the 'mt' command with the 'datcompression' option, but Ubuntu uses a version of GNU mt that doesn't allow for that option. The solution recommended to me was to use software compression instead, so I'm giving that a try.

Software compression (eg. compress/gzip/bzip2) will result in a longer time frame to get your backup to tape, also the compression is done via host operating system, which will created a higher load.

I use mt version 0.9b which support compression parameter. Did you check for?

Did you try to download a newer version of mt source code and compile it for your system?

I haven't tried a newer version. I don't plan to in the near future, as even using the software compression, the backup is still completing within the allotted time frame. This should be good enough for the time being, so I think I'm just going to leave it as is until the situation changes.