a) Configuring The OpenSSH Server
Open the /etc/ssh/sshd_config file on your favorite text editor with superuser privileges. Find the AllowTcpForwarding parameter and change its value to no.AllowTcpForwarding no
b) Restarting The OpenSSH Server
After all, restart sshd service.sudo systemctl restart sshd.service
It should give the SSH server a graceful restart.
