Thanks for filing this bug, and the excellent analysis. So it looks like the dnsmasq change was introduced here: https://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=744231d99505cdead314d13506b5ff8c44a13088
That was in response to this mailing list discussion: https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2023q4/017333.html I think we need to report this issue upstream, perhaps we can revert that commit in the meantime. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2055776 Title: After updating ubuntu, the network to which the subnet address is assigned does not become active in KVM. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/2055776/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs