The old iptables-nft package name is replaced by iptables, and the legacy backend is available as iptables-legacy. When switching packages (among iptables-nft, iptables, iptables-legacy), check for .pacsave files in /etc/iptables/ and restore your rules if needed: /etc/iptables/iptables.rules.pacsave /etc/iptables/ip6tables.rules.pacsave Most setups should work unchanged, but users relying on uncommon xtables extensions or legacy-only behavior should test carefully and use iptables-legacy if required.