Open the /etc/ssh/ssh_config file.
sudo nano /etc/ssh/ssh_config
and add the following line to the end of the file:
ServerAliveInterval 60
What this option does is to send a null packet to the server at every 60 seconds (of inactivity) to keep the SSH connection alive. You can experiment with the value, setting it to either higher or lower, depending on your system configuration. A value of 60 is a good starting point to start the experimentation.
เสร็จทำการ reload ssh 1 รอบครับ
systemctl reload ssh
