I use ssh -p8520 username@remote_host to login remote server.
Issue:
It is always connected and works properly when I am in the work place. Unfortunately, terminal freezes in 10 - 15 minutes after I connected with the remote server from home.
There's no error/timeout report on the console but the cursor cannot move any more.
When enter w to check the login users, some zombies login users are there, and I have to kill them manually.
This is quite annoying. Can anyone help me?
Answer
The ssh daemon (sshd), which runs server-side, closes the connection from the server-side if the client goes silent (i.e., does not send information). To prevent connection loss, instruct the ssh client to send a sign-of-life signal to the server once in a while.
The configuration for this is in the file $HOME/.ssh/config, create the file if it does not exist (the config file must not be world-readable, so run chmod 600 ~/.ssh/config after creating the file). To send the signal every e.g. four minutes (240 seconds) to the remote host, put the following in that configuration file:
Host remotehost
HostName remotehost.com
ServerAliveInterval 240
To enable sending a keep-alive signal for all hosts, place the following contents in the configuration file:
Host *
ServerAliveInterval 240