Bug#902026: systemd: "systemctl start systemd-timesyncd.service" kills chrony

[Francesco Poli (wintermute)]

Package: systemd
Version: 238-5
Severity: normal

Dear systemd Debian package maintainers,
it seems I found out a regression of systemd-timesyncd.

It used to refuse to start, whenever other NTP clients (such as chrony)
were used.
If I read bug #805927 correctly, now this is accomplished with
other NTP clients shipping service files with an appropriate
"Conflicts=systemd-timesyncd.service" directive.
However, this does not seem to work as expected.

Please let me explain.

I have chrony running on my system, and its service file seems
to satisfy the above requirement:

  $ cat /lib/systemd/system/chrony.service
  [Unit]
  Description=chrony, an NTP client/server
  Documentation=man:chronyd(8) man:chronyc(1) man:chrony.conf(5)
  Conflicts=systemd-timesyncd.service openntpd.service ntp.service
  After=network.target
  ConditionCapability=CAP_SYS_TIME
  
  [Service]
  Type=forking
  PIDFile=/run/chronyd.pid
  EnvironmentFile=-/etc/default/chrony
  ExecStart=/usr/sbin/chronyd $DAEMON_OPTS
  ExecStartPost=-/usr/lib/chrony/chrony-helper update-daemon
  PrivateTmp=yes
  ProtectHome=yes
  ProtectSystem=full
  
  [Install]
  Alias=chronyd.service
  WantedBy=multi-user.target


But, as soon as I issue:

  # service systemd-timesyncd start

chrony dies and systemd-timesyncd starts.

I thought that systemd-timesyncd should refrain from starting and
leave chrony alone.

I think this misbehavior happens whenever all the services are
started (e.g.: at boot, when "systemctl daemon-reexec" is issued,
and so forth...).

This is very annoying.
My expectation is that the installation of chrony should automatically
disable systemd-timesyncd.
It used to work this way in the past, but it no longer seems to be the
case...

Could you please investigate and fix this issue?
Thanks for your time.

Bye!



-- Package-specific info:

-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (800, 'testing'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.16.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages systemd depends on:
ii  adduser          3.117
ii  libacl1          2.2.52-3+b1
ii  libapparmor1     2.12-4
ii  libaudit1        1:2.8.3-1
ii  libblkid1        2.32-0.1
ii  libc6            2.27-3
ii  libcap2          1:2.25-1.2
ii  libcryptsetup12  2:2.0.2-1
ii  libgcrypt20      1.8.3-1
ii  libgpg-error0    1.31-1
ii  libidn11         1.33-2.2
ii  libip4tc0        1.6.2-1
ii  libkmod2         25-1
ii  liblz4-1         1.8.2-1
ii  liblzma5         5.2.2-1.3
ii  libmount1        2.32-0.1
ii  libpam0g         1.1.8-3.7
ii  libseccomp2      2.3.3-2
ii  libselinux1      2.8-1
ii  libsystemd0      238-5
ii  mount            2.32-0.1
ii  procps           2:3.3.15-2
ii  util-linux       2.32-0.1

Versions of packages systemd recommends:
ii  dbus            1.12.8-3
ii  libpam-systemd  238-5

Versions of packages systemd suggests:
ii  policykit-1        0.105-20
pn  systemd-container  <none>

Versions of packages systemd is related to:
pn  dracut           <none>
ii  initramfs-tools  0.130
ii  udev             238-5

-- no debconf information