Turn on the sip server, turn on and off the firewall

① Turn on the server

#cd /usr/local/sbin

#./opensipsctl start

#/etc/init.d/opensips  start

(#service opensips status)

② firewalld firewall

#systemctl stop(start) firewalld.service

#sudo firewall-cmd --state

③ufw firewall

#sudo ufw disable(enable)

#sudo ufw jams

④ Before making an ssh connection, first enable the service

#service sshd start