This is a real anomaly.
I have a client with and SBS 2003 who alternates daily between two external terabyte hard drives. These drives run the built in NT Backup through server management to back up the system drive only (C:, all data handled by another backup program).
Drive one is fine. It backs up about 30 gigs of info in a timely fashion and verifies it. Drive two takes forever and often fails. After much troubleshooting I figured out that this is because instead of backing up the system drive it is backing itself up, possibly not even skipping its own backup directory.
Both drives are running the same backup profile (which I did recreate using NTbackup and scheduled tasks instead of the server management backup, all to the same effect.) This profile explicitly excludes all drives but the c: drive. When the profile runs on the second drive it shows "C:/....[name of path that actually exists on f:]. Further, the backup size on drive two matches its own size, and increases daily as it backs up itself plus the previous backup.
I can't even tell if this is a software or a hardware issue. I think I'm out of configuration options and yet I have no evidence that the hardware is malfunctioning.
Thanks for looking