These settings can be made either
The configuration file for ssh client is /etc/ssh/ssh_config. You can open it with your favorite editor
Note: this file will set the option server wide. If you want just to set it for particular user create .ssh_config file in the home directory of the user.
There are two configuration options that have to be set in order to implement keep-alive on ssh from client side.
ServerAliveInterval - sets an interval in seconds. If no data is received from server for specified time ssh will send a message through the encrypted channel and will request a response from the server.
The second option is ServerAliveCountMax. It sets the max attempts that ssh client will send keep-alive packets to the server. If no response is received from server side for the specified count of messages the connection is closed automatically by the client.
tries to keep an ssh connection active.. if it disconnects it will automatically restart the connection