This issue can be addressed with a manual action, but first you have to dig into the scripts to diagnose the problem, and really if resolvconf is installed then it should just work.
Part of this setup involves disabling systemd-resolved, in favor of a "direct" /etc/resolv.conf, to match the network configuration of other systems at my site. We've also found resolvconf to be a good solution to allow flexibility in how the dynamic resolv.conf file is assembled. There are at least two issues that I can see here: 1. When there is more than one script in /etc/dhcp/dhclient-enter- hooks.d/ that defines the make_resolv_conf() shell function, the last definition is the one that "wins." If the "resolvconf" script is renamed to e.g. "zz-resolvconf", then it works correctly. This may be a case for renaming systemd's "resolved" script to something like "00resolved" (borrowing an idea from /etc/X11/Xsession.d/), since it is always present in an out-of-the-box install. 2. The "resolved" script takes effect if the /lib/systemd/systemd- resolved executable is present, when it should probably also check that systemd-resolved is enabled. Currently, the script runs even if systemd- resolved is not active, effectively turning into a no-op (albeit a no-op that clobbers resolvconf's functionality). That would also fix another use case, where systemd-resolved is disabled and resolvconf is absent. In that scenario, the default make_resolv_conf() function from /sbin/dhclient-script should be used. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1782275 Title: Conflict between resolvconf and systemd-resolved dhclient scripts Status in resolvconf package in Ubuntu: New Status in systemd package in Ubuntu: New Bug description: I am setting up an Ubuntu 18.04 (bionic) system with ifupdown instead of netplan, as the latter does not meet my needs. I am using resolvconf to update /etc/resolv.conf from DHCP, as in earlier releases. Unfortunately, I am not seeing /etc/resolv.conf (actually a symlink to /run/resolvconf/resolv.conf) being updated; it is only the boilerplate from /etc/resolvconf/resolv.conf.d/head with no server information appended. (My "base" and "tail" files are empty.) I poked around the scripts in /etc, and believe I have found the problem. When resolvconf is installed, the following two files are present: /etc/dhcp/dhclient-enter-hooks.d/resolvconf /etc/dhcp/dhclient-enter-hooks.d/resolved Both of these scripts define the make_resolv_conf() shell function. What I am seeing is that dhclient runs these two scripts in the (alphabetical) order shown, and as the resolved script runs second, it overwrites the resolvconf version of the shell function with its own. As a result, dhclient does not invoke the appropriate update command for resolvconf, even though the hook script was installed correctly. Normally, I would remove the package that is providing the "resolved" script, but this package is systemd, which cannot be removed. I am not sure which of the two packages (resolvconf or systemd) needs to make an accommodation for the other, but it is clear that the current approach does not work. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/resolvconf/+bug/1782275/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
