Comment 0 for bug 1913581

'resolvectl' has been introduced in systemd v239.

In ubuntu, a symlink has been created as follows:

$ ls -altr /usr/bin/systemd-resolve
lrwxrwxrwx 1 root root 10 Jul 6 2020 /usr/bin/systemd-resolve -> resolvectl

Both command can still be executed, but the symlink will eventually disapear.
It is only to accomodate the transition.

In stable releases we have systemd version lt and gt v239:

#systemd-resolve (wo/ resolvectl cmd at all):
 systemd | 229-4ubuntu21.27 | xenial-security
 systemd | 229-4ubuntu21.29 | xenial-updates
 systemd | 237-3ubuntu10 | bionic
 systemd | 237-3ubuntu10.38 | bionic-security
 systemd | 237-3ubuntu10.44 | bionic-updates

#resolvectl (with the deprecated symlink):
 systemd | 245.4-4ubuntu3 | focal
 systemd | 245.4-4ubuntu3.4 | focal-updates
 systemd | 246.6-1ubuntu1 | groovy
 systemd | 246.6-1ubuntu1.1 | groovy-updates
 systemd | 247.1-4ubuntu1 | hirsute

This 'sos' change enable 'resolvectl' as the preference but is backward compatible with 'systemd-resolve' for systemd with systemd version lt v239.

Upstream:
https://github.com/sosreport/sos/pull/2385
https://github.com/sosreport/sos/pull/2385/commits

Debian:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=979264