Test plan was updated, and yes I can and will test directly with captive portal :)
** Description changed: [ Impact ] * High impact issue, if fixed or not fixed for different reasons. - the solution provided in #1880258 was to workaround a systemd issue, and the systemd issue was a workaround due to badly configured captive portals around the world (DNS resolution issue). The side effect is that many company firewall blocks invalid DNS queries, such as connectivity-check.ubuntu.com. If the NM fails to check the URI, the interface never goes ONLINE, and plugging a local network device (such as an embedded board), has the side effect of moving the default route to an higher priority network (cable over wifi has higher priority) and the consequence of having a broken internet, as well as annoying popups on Ubuntu saying that internet is not available (despite it being there) That said, bug https://bugs.launchpad.net/bugs/1880258 was opened to fix a critical issue with flooding of systemd logs (fixed in parallel by making them DEBUG messages), so the issue now at least seems to be related to sending two DNS queries instead of one (a much lower priority issue!) Original message: It is unclear why the change on https://launchpad.net/ubuntu/+source/network-manager/1.54.3-2ubuntu3 is wanted, the changelog doesn't document the motivation. Wouldn't it create more traffic again, https://bugs.launchpad.net/bugs/1880258 explains the initial motivation Let's block proposed migration until we get extra details [ Test plan ] - * update the configuration of Ubuntu network manager URI to connectivity-check.ubuntu.com, removing the "." at the end, and check if systemd is flooded - and with tcpdump how many DNS queries are sent out + * Install the proposed package, and check with tcpdump how many DNS + queries are sent out - Observing the issue and the fix requires 3 terminals: + Observing the issue and the fix requires 2 terminals: 1. tcpdump -i any 'port domain' - 2. journalctl --boot -u systemd-resolved -f + 2. nmcli c down "Wired connection 1"; nmcli c up "Wired connection 1" + => observe the NXDOMAIN noise over a couple few minutes - 3. nmcli c down "Wired connection 1"; nmcli c up "Wired connection 1" - => observe the NXDOMAIN noise over a couple few minutes + * Observe with captive portal [ Where problems could occur ] * There might be still some broken captive portals, but right now at least on Ubuntu 26.04 I don't see many DNS queries sent out, so people should have already complained by now. We need at least to patch back NM where systemd is not sending additional DNS queries, because this way we sync with Debian both package behaviours without risk of regressions. If we find systemd to have still the workaround, probably the safe thing to do is to leave things as-is [ Other Info ] * For now resolute looks really fine, tcpdump is showing only one call to the DNS server * I added the people affected by 1880258 to this bug so we can have some broader testing -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2148643 Title: [SRU] connectivity-check.ubuntu.com URL change? To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/2148643/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
