@Ryutaroh - could you test [1] if it gets you around this bug (1886811) and if bug 1890881 is present in focal as well?
[1]: https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/4197 -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1886811 Title: systemd complains Failed to enqueue loopback interface start request: Operation not supported Status in QEMU: Fix Committed Status in qemu package in Ubuntu: Fix Released Status in qemu source package in Focal: New Status in qemu package in Debian: Fix Released Bug description: This symptom seems similar to https://bugs.launchpad.net/qemu/+bug/1823790 Host Linux: Debian 11 Bullseye (testing) on x84-64 architecture qemu version: latest git of git commit hash eb2c66b10efd2b914b56b20ae90655914310c925 compiled with "./configure --static --disable-system" Down stream bug report at https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=964289 Bug report (closed) to systemd: https://github.com/systemd/systemd/issues/16359 systemd in armhf and armel (both little endian 32-bit) containers fail to start with Failed to enqueue loopback interface start request: Operation not supported How to reproduce on Debian (and probably Ubuntu): mmdebstrap --components="main contrib non-free" --architectures=armhf --variant=important bullseye /var/lib/machines/armhf-bullseye systemd-nspawn -D /var/lib/machines/armhf-bullseye -b When "armhf" architecture is replaced with "mips" (32-bit big endian) or "ppc64" (64-bit big endian), the container starts up fine. The same symptom is also observed with "powerpc" (32-bit big endian) architecture. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1886811/+subscriptions
