Ubuntu-iptables configuration
The system installed by default by ubuntu-server does not have a firewall iptables installed
Only the configuration file: / etc/iptables.rules
However, it doesn't matter. You can edit the configuration as follows:
# vi / etc/iptables.rules adds its own rules
Use the command to save:
# iptables-restore-c / etc/iptables.rules is effective immediately. (no need to install iptables)
# iptables-L-n View rules
