Hello again, another observation: In Fedora 29, firewalld also defaults to the iptables backend, and I get the same error noise in "systemctl status firewalld". But "--reload" works.
The main differences that I can see is: * kernel: 4.18 on Debian unstable, 4.19.2 on Fedora 29 * iptables: 1.8.2 on Debian unstable, 1.8.0 on Fedora 29 I downgraded F29 to 4.18 as well [1], and the bug does not happen. Thus I didn't report that upstream yet. Martin [1] https://koji.fedoraproject.org/koji/buildinfo?buildID=1163180
