update-alternatives --set fails because the base image only registers iptables-legacy as an alternative. The iptables-nft binary (/usr/sbin/iptables-nft) exists but isn't in the alternatives database. Direct ln -sf bypasses this.
update-alternatives --set fails because the base image only registers iptables-legacy as an alternative. The iptables-nft binary (/usr/sbin/iptables-nft) exists but isn't in the alternatives database. Direct ln -sf bypasses this.