Firewalld

firewalld is a firewall daemon developed by Red Hat. It uses nftables by default.

Firewalld provides a dynamically managed firewall with support for network/firewall zones that define the trust level of network connections or interfaces. It has support for IPv4, IPv6 firewall settings, ethernet bridges and IP sets. There is a separation of runtime and permanent configuration options. It also provides an interface for services or applications to add firewall rules directly.

pacman -S firewalld ipset

systemctl enable --now firewalld.service

After every change firewalld should always be reloaded:

firewall-cmd --reload

firewall-cmd --change-interface=YOUR-INTERFACE --zone=home --permanent

or

firewall-cmd --add-interface=YOUR-INTERFACE --zone=home --permanent
firewall-cmd --remove-interface=YOUR-INTERFACE --zone=home --permanent

or

nmcli connection show
nmcli connection modify 'NAME' connection.zone home

Check if the favoured service is available by default ls /usr/lib/firewalld/services/ or ls /usr/lib/firewalld/services/ | grep 'YOUR-SERVICE. Otherwise, you have to create your own.

firewall-cmd --add-service=kdeconnect --zone=home --permanent
firewall-cmd --remove-service=dhcpv6-client --zone=home --permanent

firewall-cmd --new-service=YOUR-NEW-SERVICE --permanent
firewall-cmd --service=YOUR-NEW-SERVICE --set-description=YOUR-NEW-SERVICE --permanent
firewall-cmd --service=YOUR-NEW-SERVICE --set-short=YNS --permanent
firewall-cmd --service=YOUR-NEW-SERVICE --add-port=1234/tcp --permanent

firewall-cmd --add-service=YOUR-NEW-SERVICE --zone=home --permanent

firewall-cmd --add-port=80/tcp --zone=home --permanent
firewall-cmd --remove-port=80/tcp --zone=home --permanent

firewall-cmd --add-forward-port=port=12345:proto=tcp:toport=22:toaddr=192.168.1.50 --zone=home --permanent
firewall-cmd --remove-forward-port=port=12345:proto=tcp:toport=22:toaddr=192.168.1.50 --zone=home --permanent

firewall-cmd --new-zone=YOUR-ZONE --permanent
firewall-cmd --delete-zone=YOUR-ZONE --permanent

firewall-cmd --add-masquerade --zone=home --permanent
firewall-cmd --remove-masquerade --zone=home --permanent

firewall-cmd --new-policy NAT_int_to_ext --permanent
firewall-cmd --policy NAT_int_to_ext --add-ingress-zone wireguard --permanent
firewall-cmd --policy NAT_int_to_ext --add-egress-zone home --permanent
firewall-cmd --policy NAT_int_to_ext --set-target ACCEPT --permanent

firewall-cmd --get-active-zones

firewall-cmd --list-all-zones
firewall-cmd --info-zone=home

firewall-cmd --get-zone-of-interface=YOUR-INTERFACE

firewall-cmd --get-services
firewall-cmd --list-services --zone=home
firewall-cmd --info-service YOUR-SERVICE

Self created:

ls /etc/firewalld/services/

Default:

ls /usr/lib/firewalld/services/

firewall-cmd --list-ports --zone=home

firewall-cmd --list-rich-rules --zone=home

ls /usr/lib/firewalld/policies/
ls /etc/firewalld/policies/

Only if you are running a desktop environment on your server or for your desktop computer.

The GUI can also be useful if you need to quickly change zones at specific network locations.

pacman -S python-pyqt6

firewall-applet

nano ~/.config/firewall/applet.conf

[General]
notifications=true
show-inactive=true

The permanent option --permanent can be used to set options permanently. These changes are not effective immediately, only after service restart/reload or system reboot. Without the --permanent option, a change will only be part of the --runtime configuration.

firewall-cmd --runtime-to-permanent