Im in the same exact boat. I have a fresh install of BE 12.5 (with sp1 and hotfix,) superloader 3 (lto3,) windows 2008 (x64 std) and I am having a terrible time getting BE to catalog or run backups. Ive tried all the normal SCSI-related troubleshooting (different drivers, add/remove hardware, check cable, etc etc) and this is really perplexing. I can inventory and scan fine, so its controlling the changer properly, but I keep getting the unable to allocate media errors when trying to catalog and backup.
What is totally bizarre is that I was able to get it to catalog one sinlge tape, and I can write backups to it from BE, but they are extremely slow. Im using an adaptec 29160, and I had changed the Byte sync-rate down to 40 MB/sec on the one time that it cataloged properly. Ive seen this type of issue in the past, where I had to force a slower sync-rate to get reliable backups (using Netbackup and an LTO2 qualstar device, though.)
What is even more frustrating is that all the SCSI operations are running flawlessly (using tracer.exe) with not one single error. I have to believe this is some stupid driver issue or something with 12.5 and windows 2008....
BTW, it does seem that it writes faster to the one tape that it cataloged when I increased the number of buffers from the drive config in BE. It will wtill write about 80 MB instantly, then begin to write incredibly slow (literally probably 100KB/sec.) With the default setting, it will write slower the whole time.
I hate SCSI device issues like this....how frustrating.
