we have an old unix based system, which is no longer supported. It supposedly is setup to do an auto backup nightly. Is there a way to check to be sure this is running. Can you check for a last backup date?
That depends entirely on how you are backing up the system.
What version of Unix is it? Try the `uname -a` command
Are you reading the e-mail in the root account? Try the `mailx` command
What program are you using to back up the system? Try reading root's crontab file with the `crontab -l` command and the system crontab file with the `cat /etc/crontab` command