This example set the maximum time to 15 minutes idle, so open sshd_config
file with your favorite text editor as root. In our case vi:
vi /etc/ssh/sshd_config
And be sure this options are set:
ClientAliveInterval 900 ClientAliveCountMax 0
This way after 900 seconds, the ssh session will be terminated, with
no keep alive package even being sent. You may adjust the idle time with
ClientAliveInterval
, set it in seconds to the time you think is enough for your users.
Also be sure the parameter is enabled:
TCPKeepAlive yes