Originally Posted by deacon912
I am using a using RHEL5 for ...<SNIP>...
There are several good solutions available depending on how you want to force the logout exactly.
The most simple solution if your users use bash or korn shell is to set the TMOUT variable in the system wide bashrc.
echo "export TMOUT=3600" >> /etc/bashrc
echo "readonly TMOUT" >> /etc/bashrc
Should work on RHEL4/5, On most debian derivatives you could do the same with the /etc/bash.bashrc file. The number is the number of seconds... a few round and handy useful values 300 (5 minutes), 1800 (30 minutes), 3600 (1 hour), 10800 (3 hours), and 86400 (24 hours). The readonly line prevents the users from altering it once they figure out what is going on.
If the users are SSHing into the system some versions of sshd will allow you to set "IdleTimeout" (unfortunately, most modern versions do not allow this.)
The alternative beyond that point is to use a watchdog program for ssh or a daemon to monitor idle time as suggested by a previous response.
Good luck and I hope it helps!