Package: systemd-resolved
Version: 251.3-2~exp1
Severity: critical
(filing the bug as critical since it "makes unrelated software on the
system (or the whole system) break", feel free to downgrade)
Dear developers,
The new systemd-resolved package takes over /etc/resolv.conf, and
unconditionally makes it a symlink it to
/run/systemd/resolve/stub-resolv.conf. Moreover, after the package is
removed, the symlink is also removed, leaving the system with no
/etc/resolv.conf, and thus, a broken DNS resolution.
/etc/resolv.conf is not considered as a conffile since technically, it
doesn't belong to any package (and is not listed as a conffile by
systemd-resolved, which treats it as a normal file), but if it's
considered as a configuration file (it's located in /etc after all), I
believe this behavior severely transgresses Debian Policy 10.7.3 on both
points ("local changes must be preserved during a package upgrade" and
"configuration files must be preserved when the package is removed").
One (conservative) solution would be to not touch /etc/resolv.conf at
all, leaving the users create the symlink to
/run/systemd/resolve/stub-resolv.conf (or
/run/systemd/resolve/resolv.conf) themselves. This would solve both
transgressions at once. One could argue that it wouldn't make sense to
install systemd-resolved and not use it in /etc/resolv.conf, but the
service would still provide the bus and glibc APIs.
If /etc/resolv.conf is not considered a configuration file, and this new
behavior does not transgresses the Debian Policy, then the package
should at least leave the system with a working /etc/resolv.conf file
after removal, for example by copying the contents of
/run/systemd/resolve/resolv.conf (optionally stripping comments and
empty lines) in maintainers scripts.
Regards,
--
Raphaël Halimi
