Set Interactive Session Timeout

Description

Setting the TMOUT option in /etc/profile ensures that all user sessions will terminate based on inactivity. The value of TMOUT should be exported and read only. The TMOUT setting in a file loaded by /etc/profile, e.g. /etc/profile.d/tmout.sh should read as follows:

typeset -xr TMOUT=

or

declare -xr TMOUT=

Using the typeset keyword is preferred for wider compatibility with ksh and other shells.

Rationale

Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended.