Good news, the network-manager SRU is not broken or wrong, but an additional SRU, on systemd, is needed to actually fix this bug.
I got a hint from Iain Lane (Laney, thank you very much) to the following fix in systemd upstream: https://github.com/systemd/systemd/commit/a97a3b256 and backported it to Bionic's systemd package (debdiff attached). With the network-manager SRU from -proposed attached plus the patched systemd package installed the problem goes away. If I repeat the test of [Test Case] (after a reboot) the DNS requests to any of the VPN's domains go actually only to the VPN's DNS. ** Patch added: "systemd_237-3ubuntu10.21_237-3ubuntu10.22.debdiff" https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1754671/+attachment/5262723/+files/systemd_237-3ubuntu10.21_237-3ubuntu10.22.debdiff ** Also affects: systemd (Ubuntu) Importance: Undecided Status: New ** Changed in: systemd (Ubuntu) Status: New => Fix Released ** Changed in: systemd (Ubuntu Bionic) Status: New => Triaged ** Changed in: systemd (Ubuntu) Importance: Undecided => High ** Changed in: systemd (Ubuntu Bionic) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1754671 Title: Full-tunnel VPN DNS leakage regression To manage notifications about this bug go to: https://bugs.launchpad.net/network-manager/+bug/1754671/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
