We have a client with a new HP ProLiant ML350 G5; SATA RAID 5 array; HP tape backup; Buffalo Technologies DriveStation external 500gb HD. About every 3-4 weeks, the BackupAssist-based backup (which uses NT Backup) to the external drive stops at some point during the backup with a red light on the backup drive. At that point, Exchange and SBS stops connecting to Outlook clients and is unavailable for incoming/outgoing mail via port 25. Also, the server is unavailable to login to either locally or RDP/VNC.
The last time this occurred, the server was forced to shutdown manually via the power switch, which we didn't want to do, but there was no other alternative we could come up with. The big problem we encounter, though, is during the time the server is 'mostly' unavailable several Thomson-based accounting programs (like Client Solutions) allow access to specific client Microsoft Access-based databases. After forcing the server to quit, any individual client databases that were open during that 'mostly' not working time get corrupted, even though the Thomson programs have been closed properly on the client end. Obviously they are not properly closing on the server end.
Other piece of information is that we had this problem once or twice on the previous HP ProLiant ML310 server that was recently replaced. It used the same HP tape backup and Buffalo Technologies HD as the new server.
Can we safely assume that the hard drive in question is the most likely culprit, given the circumstances? We have never had an issue like this with similarly configured servers at other client offices. Before we tell the client they need to buy a new hard drive, we would like to verify that it sounds reasonable that this is the problem. Given that we have had identical problems on two independent servers, it seems like the hard drive is the most-likely problem. BackupAssist software just schedules for NT Backup, so I am less likely to suspect that.
Any other ideas?