Comment 2 for bug 1898000

Hrm I got to test this now and I can't reproduce with:

Groovy
root@g:~# grep OPT /etc/default/chrony
DAEMON_OPTS="-F -1 -x"
root@g:~# systemctl restart chrony; systemctl status chrony | grep 'sbin\/chronyd'
             ├─118154 /usr/sbin/chronyd -F -1 -x
             └─118155 /usr/sbin/chronyd -F -1 -x

Focal
root@f:~# grep OPT /etc/default/chrony
DAEMON_OPTS="-F -1 -x"
root@f:~# systemctl restart chrony; systemctl status chrony | grep 'sbin\/chronyd'
             ├─80336 /usr/sbin/chronyd -F -1 -x
             └─80337 /usr/sbin/chronyd -F -1 -x

Hmm, maybe my containers I currently use are "too capable"

The script does two things:
1. it checks if it is running in a container
OR
2. it checks if it misses cap_sys_time

If 1 || 2 are true the service would (by default) fail to run at all.
The wrapper automatically adds -x in that case.

So if 1 || 2 you'll see:
  "Adding -x as fallback disabling control of the system clock, see
  /usr/share/doc/chrony/README.container to override this behavior"

But when you add -x in the OPTs yourself it should still be ok.
It runs a getopt loop if there is a -x.
If it is set it does not go into any of the later checks and runs chrony as you told it.

Test on non privileged container
default:
             ├─1459 /usr/sbin/chronyd -F -1 -x
             └─1460 /usr/sbin/chronyd -F -1 -x
...
Oct 05 11:27:20 g-chrony chronyd-starter.sh[1454]: Warning: Running in a container, likely impossible and unintended to sync system clock
Oct 05 11:27:20 g-chrony chronyd-starter.sh[1454]: Adding -x as fallback disabling control of the system clock, see /usr/share/doc/chrony/README.container to override this behavior

Adding -x to the options still does not break it ... hmm:

Groovy:
root@g-chrony:~# grep OPT /etc/default/chrony
DAEMON_OPTS="-F -1 -x"
root@g-chrony:~# systemctl restart chrony; systemctl status chrony | grep 'sbin\/chronyd'
             ├─1688 /usr/sbin/chronyd -F -1 -x
             └─1689 /usr/sbin/chronyd -F -1 -x

Focal:
root@f-chrony:~# grep OPT /etc/default/chrony
DAEMON_OPTS="-F -1 -x"
root@f-chrony:~# systemctl restart chrony; systemctl status chrony | grep 'sbin\/chronyd'
             ├─2221 /usr/sbin/chronyd -F -1 -x
             └─2222 /usr/sbin/chronyd -F -1 -x

Still ok.
Could you add set -x to /usr/lib/systemd/scripts/chronyd-starter.sh and let me know why the getopt loop might not work for you?

From /usr/lib/systemd/scripts/chronyd-starter.sh:
# Check if -x is already set manually, don't process further if that is the case
X_SET=0
while getopts ":x" opt; do
    case $opt in
        x)
            X_SET=1
            ;;
    esac
done