Allow intra-zone traffic with firewalld

gistfile1.txt

#!/bin/sh

interfaces=$(firewall-cmd --info-zone=internal | grep interfaces | cut -d' ' -f 4-)

for a in $interfaces; do
   for b in $interfaces; do
     if [ $a != $b ]; then
       echo "$a to $b"
       firewall-cmd --permanent --direct --add-rule ipv4 filter FWDI_internal_allow 0 -o $a -i $b -j ACCEPT

       echo "$b to $a"
       firewall-cmd --permanent --direct --add-rule ipv4 filter FWDI_internal_allow 0 -o $b -i $a -j ACCEPT
     fi
   done
done
firewall-cmd --reload