Question : Problem: Slow Backup times - 60MB per minute job rate

I recently had to change my backup tape drive as my old one failed. However im currently only getting 60MB per minute instead of the 400MB per minute i used to achieve.

The drive is a LTO 2 on a raid card along with other devices, i know that its not recommended but my pervious drive was as well and it worked fine.

I have used the latest veritas drives for the drive itself and it knows what it is and is working just at a slow rate. Its taking in excess of 42 hours to back up 125GB.

The drive is only backing up the server that it is connected to.

Any help would be appricaited.

Answer : Problem: Slow Backup times - 60MB per minute job rate

Hey mate
You might be suffering from the 'slowest device on the chain' syndrome. This is an old condition that used to happen when you connected fast scsi devices in the same bus with slow scsi devices, which meant the fast scsi device will slow down to the lowest speed to that it would not clash as scsi is daisy chained.

You could if possible remove all other devices and perform a test backup and see how that goes. Then reconnect one device at a time and re-test again. Also take a look at the firmware level of the tape LTO. it might be suspect and needs to be flashed to newer if available.

Also as mentioned above, look at the scsi drivers and update them.

This should solve your problems
Morci