I could reproduce the issue by building git v1.8.5 and the issue was fixed after cherry-picking "iptables-nft: fix basechain policy configuration"
$ git log commit 8d985eb4eb7a23fd98b75d71179af40169144cc5 (HEAD -> bug1898547) Author: Pablo Neira Ayuso <pa...@netfilter.org> Date: Fri Oct 2 13:44:36 2020 +0200 iptables-nft: fix basechain policy configuration Previous to this patch, the basechain policy could not be properly configured if it wasn't explictly set when loading the ruleset, leading to iptables-nft-restore (and ip6tables-nft-restore) trying to send an invalid ruleset to the kernel. Signed-off-by: Arturo Borrero Gonzalez <art...@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org> commit 14ac250946289e280fb09ef978a45042871275b0 (tag: v1.8.5) Author: Pablo Neira Ayuso <pa...@netfilter.org> Date: Wed Jun 3 11:37:52 2020 +0200 configure: bump version for 1.8.5 release Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org> ** Also affects: iptables (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1898547 Title: neutron-linuxbridge-agent fails to start with iptables 1.8.5 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/iptables/+bug/1898547/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs