Some time ago, I moved to an LTO3 external backup unit on our main server
(NW6.5 SP4A), from an LTO1. This was due to the amount of data we needed
to fit on the tape. The server itself only has an Adaptec 160 SCSI card,
which is not really matched to the LTO3 unit (it should be a 320).

Backups ran at around 1700 Megabytes/minutes, but every now and then, we'd
hit a hardware error during backup. This is with BE 9.10. I'd unload and
reload BE and the tape drivers, and then the backups ran OK, but this time
at around 1200 Megabytes/minutes. There were no failures at this speed. I
put the problems down to the mismatch of the 320 device/160 card, and the
slower speed the backups reached after unloading/reloading the drivers
caused no problems at all, for around 8 months.

However, after a recent server reboot, the backup speeds are back to 1700
MB/Min, we keep hitting these hardware errors again. No matter what I try,
I can't get the speeds to go back down to the "safe" 1200 MB/min.

Does anyone know of a way to throttle backup speeds within BE? An unusual
question maybe, but any help would be much appreciated.