Ubuntu Iptables Configuration on Startup

iptables ubuntu

• Save iptables rules

  sudo sh -c "iptables-save > /etc/iptables.rules"
  

• Load iptables rules after startup (script /etc/network/if-pre-up.d/iptablesload)

  #!/bin/sh
  iptables-restore < /etc/iptables.rules
  exit 0
  

• Save iptables rules after interface shutdown (script /etc/network/if-post-down.d/iptablessave)

  #!/bin/sh
  iptables-save -c > /etc/iptables.rules
  # remove virbr0 (192.168.122.0/24) rules since it will be regenerated after restart
  sed -i '/192.168.122/d' /etc/iptables.rules
  if [ -f /etc/iptables.downrules ]; then
   iptables-restore < /etc/iptables.downrules
  fi
  exit 0
  

  refer: https://help.ubuntu.com/community/IptablesHowTo

Written on October 4, 2018