Specs for serverbackup

Look at the files in backup directory
Extract the dates from the filenames
Check whatever a tape drive is on and contains a tape
Check whatever the external harddrive is connected
- If it is, try to mount it
- If mount fails, abort script and write error log
Copy the latest backup to tape drive and external harddrive
Write everything to a logfile (script will run headless)
- No, doesn't do that. Instead write all error to stderr and normal output to stdout