resolvconf should never touch /etc/resolv.conf in Ubuntu; all DNS configuration from resolvconf, ifupdown, and dhclient should always be fed directly to systemd-resolved.

Bug #1874337 reported by Steve Langasek
This bug affects 1 person
Affects Status Importance Assigned to Milestone
ifupdown (Ubuntu)
resolvconf (Ubuntu)
systemd (Ubuntu)

Bug Description

systemd-resolved is a standard component of Ubuntu in 20.04. We should not have packages in the archive - some of which may be installed on users' systems as a result of upgrading from previous releases - that cause the handling of DNS resolution to diverge from the default.

This means that:

- the dhclient hook that picks up DNS settings should only feed settings directly to resolved, and not via resolvconf.
- resolvconf must not change the target of /etc/resolv.conf and on upgrade must correct it.
- resolvconf must feed its settings reliably into resolved rather than pulling resolved settings into resolvconf.
- systemd should not ship a dhclient hook at all because dhclient is not used by any systems that use netplan for network management, it is only needed for compatibility on upgrade with ifupdown; so move the hook to the ifupdown package.

Related branches

tags: added: id-5d8b46e355320863b343b291
Revision history for this message
Dimitri John Ledkov (xnox) wrote :

I have prepared xenial containers (last ones that used ifupdown / resolvconf by default) and configured it with:
- default resolvconf & dhcp acquired dns
- above, but with an extra dns nameserver specified in eni
- with resolvconf removed and static resolv.conf configuration
- with dhclient removed and static ip configuration

I've staged above updates in a bileto PPA and will execute upgrade to bionic, then upgrade to focal + bileto PPA.

The expectation is for every configuration above, that the configuration survives the upgrade, and dns configurations still work.

Dan Streetman (ddstreet)
tags: added: resolved-resolvconf
To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Other bug subscribers