( 1) opening port status View
Queries have open ports netstat - ANP check whether the specified port has been opened Firewall -cmd --query-Port = 666 / tcp prompt yes, indicate on; no means is not turned on.
(2) View firewall status
Check firewall status systemctl status firewalld
open the firewall systemctl start firewalld
turn off the firewall systemctl stop firewalld
open the firewall service firewalld start
If they are unable to open the
first use: systemctl unmask firewalld.service
then: systemctl start firewalld.service
( 3) External port development
Adds the specified ports need to be open: Firewall -cmd --add-Port = 123 / tcp - Permanent port reloaded added: Firewall -cmd - reload query whether the port open success: Firewall -cmd --query-Port = 123 / TCP
( 3) Removes the specified port
firewall-cmd --permanent --remove-port=123/tcp
Installation iptables -services:
iptables- install yum Services
into the following directory to be modified:
/ etc / sysconfig / iptables