nftables
From wiki
nftables is the new firewall of the linux kernel.
Prerequisite
It is recommended to install the kernel from Jessie Backports.
Install
# apt install nftables
Enable
Warning: It is recommended that you test your firewall before enabling it at boot time. An incorrectly configured firewall can lock you out of your machine.
# systemctl enable nftables
It the script output `update-rc.d: error: nftables Default-Start contains no runlevels, aborting.`, don’t worry. The firewall is correctly enabled in systemd. This is bug #804648.