centos staff

centos staff

//centos open port
firewall-cmd --zone=public --permanent --add-port=6222/udp

//network test
netcat -u -z -n -v host port
-u udp | tcp
-z scan port range
-n skip dns
-v verbose info
-l listen port

//centos firewall command
firewall-cmd --state
  view status of firewalld service (systemctl status firewalld)
firewall-cmd --zone=public --list-all
  gets all info for the “public” zone
firewall-cmd --list-all-zones
  shows all info for all zones
firewall-cmd --zone=public --add-port=80/tcp --permanent
  adds port 80 to public zone
firewall-cmd --zone=public --add-service=http --permanent
  adds service http to public zone
firewall-cmd --reload
  run this after making changes
firewall-cmd --zone=public --remove-port=80/tcp --permanent
  to remove port 80 from public zone
firewall-cmd --get-default-zone
  shows default zone for firewall
firewall-cmd --get-active-zones
  zones where network interfaces or sources are assigned