Firewall related under CentOS7

This article is for personal notes only

• Iptables related: (After changing the configuration, you need to run /etc/rc.d/init.d/iptables save and service iptables restart to make the configuration take effect)
  
  • iptables-save (Save the currently changed firewall rules, remember to run the last rule after changing the rules, otherwise the configuration will be lost after restart)
  • iptables -L (list current firewall rules)
    
  • iptables -F (clears the rules of all rule chains in the preset table filter)
  • iptables -X (clears the rules in the user-defined chain in the default table filter)
  • iptables -P [INPUT/OUTPUT/FORWARD] [DROP/ACCEPT]
  • iptables -A [INPUT/OUTPUT/FORWARD] -p tcp –dport [0-n] -j [DROP/ACCEPT]
  • Allow icmp packets to pass to allow ping
  • iptables -A OUTPUT -p icmp -j ACCEPT
  • iptables -A INPUT -p icmp -j ACCEPT
  • Only allow the specified ip to access a port (for example: specify 172.31.18.47 to access port 6379)
  • iptables -I INPUT -p tcp –dport 6379 -j DROP
  • iptables -I FORWARD -p tcp –dport 6379 -j DROP
  • iptables -I INPUT -s 172.31.18.47/24 -p tcp –dport 6379 -j ACCEPT
  • iptables -I FORWARD -s 172.31.18.47/24 -p tcp –dport 6379 -j ACCEPT
  • turn off firewall
  • systemctl stop firewalld.service
  • systemctl disable firewalld.service