Firewal Linux aka iptables

firewall.sh

#show all rules in a table ; you can use alternatively -L
sudo iptables -S
#show rule number in each of the 3 possible cases: INPUT OUTPUT FORWARD
sudo iptables -L --line-numbers
#delete a rule with a number; syntax: iptables -D <OUTPUT|INPUT|FORWARD> <line_number>
sudo iptables -D OUTPUT 3
#delete all rules in a chain ;chain= INPUT, OUTPUT or FORWARD
sudo iptables -F INPUT  
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