I have a similar issue (high throughput for most backups, but not for all) but it is the backup of the First Storage Group of Exchange 2003 that is slow with a throughput of 3.2 MB/minute. The odd thing is that the First Storage Group backed up at the rate of 70MB/minute for the first few backups I have performed, while the last two backups ran at the rate of 3.2MB/minute.
12/21/06 update - if I backup the First Storage Group to the hard drive of the Media server (vs. the REV drive on the Media server) the throughput is 585MB/min.
Message was edited by:
Tim Colvin
12/29/06 update - Problem solved. The computer we tried to use the REV drive on had USB 1.1. We added a PCI card with USB 2.0 to increase the speed. Since the backups to REV were not working I switched them over to backup to the hard drive. My plan was to copy the backup files to the REV drive from the hard drive until I could resolve the issue of backing up straight to the REV drive. Lo and behold about half of the backup files received an I/O error when copying to the REV disk. I moved the REV drive to another computer - one that had USB 2.0 (without the need for the USB PCI card) - and no longer received the I/O errors when writing to the REV drive. (The I/O errors were not reported in the Event Viewer of the PC with the USB card.)
I have since installed Backup Exec to the PC with "native" USB 2.0 support and have backed up two nights in a row without any errors or slow throughput issues.
For the record, the USB card we had:
ULTRA 6 Port USB 2.0 PCI CardMessage was edited by:
Tim Colvin