Q: How do I fix the SCSI tape drive errors I encounter when backing up the /proc directory?

I have a system with an HP 1599 SCSI internal tape drive. Everything worked fine until I tried to do a complete system backup.

Here's the tar error:

proc/bus/pci/00/
proc/bus/pci/00/13.0
proc/bus/pci/00/11.0
proc/bus/pci/00/07.3
proc/bus/pci/00/07.2
proc/bus/pci/00/07.1
proc/bus/pci/00/07.0

tar: Cannot write to /dev/st0: Input/output error
tar: Error is not recoverable: exiting now

And here's the error that shows up in the system logs:

Nov 28 11:42:36 aika2 kernel:
ncr53c810a-0: SCSI parity error detected: SCR1=65 DBC=50000000 SSTAT1=7
Nov 28 11:42:36 aika2 kernel: ncr53c810a-0-<4,0>: M_REJECT sent for 80.
Nov 28 11:42:36 aika2 kernel: st0: Error with sense data: extra data not valid
Current error st09:00: sense key Aborted Command
Nov 28 11:42:36 aika2 kernel: Additional sense indicates Invalid message
error.

A: Exclude the /proc directory from your backups. It is a virtual filesystem, storing information on the status of your hardware and all running tasks.