src/systemctl/systemctl.c | 6 2 + 4 - 0 !
1 file changed, 2 insertions(+), 4 deletions(-)

 also redirect to update-rc.d when not using .service

I.e. make systemctl enable rsyslog work (previously, only systemctl
enable rsyslog.service)

src/systemctl/systemctl.c | 11 5 + 6 - 0 !
1 file changed, 5 insertions(+), 6 deletions(-)

 =?utf-8?q?systemctl=3a_don=e2=80=99t_skip_native_units_when_enabl?=
 =?utf-8?q?ing/disabling_sysv_units?=

src/systemctl/systemctl.c | 47 46 + 1 - 0 !
1 file changed, 46 insertions(+), 1 deletion(-)

 run update-rc.d defaults before update-rc.d <enable|disable>

Closes: #722523

src/login/logind-core.c | 6 6 + 0 - 0 !
1 file changed, 6 insertions(+)

 =?utf-8?q?don=e2=80=99t_try_to_start_autovt_units_when_not_runnin?=
 =?utf-8?q?g_with_systemd_as_pid_1?=

Closes: #726466

src/timedate/timedated.c | 94 93 + 1 - 0 !
1 file changed, 93 insertions(+), 1 deletion(-)

 =?utf-8?q?timedated=3a_don=e2=80=99t_rely_on_/usr_being_mounted_i?=
 =?utf-8?q?n_the_initrd?=
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit

This reverts commit 92c4ef2d357baeef78b6f82f119b92f7ed12ac77

We dont have /usr mounted in the initramfs yet in Debian, so lets
support split usr by copying the file instead of symlinking if
necessary, for now.

Closes: #726256

src/hostname/org.freedesktop.hostname1.service | 2 1 + 1 - 0 !
src/locale/org.freedesktop.locale1.service | 2 1 + 1 - 0 !
src/login/org.freedesktop.login1.service | 2 1 + 1 - 0 !
src/timedate/org.freedesktop.timedate1.service | 2 1 + 1 - 0 !
4 files changed, 4 insertions(+), 4 deletions(-)

 make logind/hostnamed/localed/timedated d-bus activatable

We want to use those services outside of systemd, so we make them
activatable via D-Bus.

src/login/org.freedesktop.login1.service | 2 1 + 1 - 0 !
1 file changed, 1 insertion(+), 1 deletion(-)

 launch logind via a shell wrapper

We need to setup the cgroupfs mount and the runtime directory before
starting logind. Use a shell script which is triggered by the D-Bus
service.

src/login/pam_systemd.c | 4 0 + 4 - 0 !
1 file changed, 4 deletions(-)

 start logind on demand via libpam-systemd

Don't make pam_sm_open_session() a NOP if logind is not running. Trying
to access logind via D-Bus will start it on demand.

src/locale/localed.c | 212 114 + 98 - 0 !
1 file changed, 114 insertions(+), 98 deletions(-)

 update localed to use the debian config files

Prefer /etc/default/locale over /etc/locale.conf when writing the locale
configuration and use /etc/default/keyboard instead of
/etc/X11/xorg.conf.d/00-keyboard.conf.

Path courtesy of Steve Langasek.

src/udev/udev.conf | 3 3 + 0 - 0 !
1 file changed, 3 insertions(+)

 add note to udev.conf that changes to that file require a rebuild of
 the initramfs

Based on debian/patches/udev_conf_comments from the old udev package.

tmpfiles.d/tmp.conf | 4 2 + 2 - 0 !
1 file changed, 2 insertions(+), 2 deletions(-)

 bring tmpfiles.d/tmp.conf in line with debian defaults

Closes: #675422

Makefile.am | 3 1 + 2 - 0 !
units/tmp.mount | 3 3 + 0 - 0 !
2 files changed, 4 insertions(+), 2 deletions(-)

 =?utf-8?q?don=e2=80=99t_mount_/tmp_as_tmpfs_by_default?=
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit

by adding an [Install] section to tmp.mount and removing the
local-fs.target.wants symlink.

Users can use systemctl enable tmp.mount to enable mounting /tmp after
the next reboot and systemctl start tmp.mount to get /tmp mounted as
tmpfs right now (beware, files currently in /tmp will not be visible
anymore afterwards).

tmpfiles.d/legacy.conf | 4 2 + 2 - 0 !
1 file changed, 2 insertions(+), 2 deletions(-)

 fix up tmpfiles.d permissions properly

src/udev/udev-event.c | 41 37 + 4 - 0 !
1 file changed, 37 insertions(+), 4 deletions(-)

 revert "udev: network device renaming - immediately give up if the
 target name isn't available"

This reverts commit 97595710b77aa162ca5e20da57d0a1ed7355eaad.

Since we are keeping the old persistent network interface naming for
now, and make the new naming scheme [1] explictly opt-in [2], re-apply
this old hack to make the renaming less likely to fail.

[1] http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/
[2] d5051f7666e25ecf2b32c7076ce18c1de969d01b

src/udev/net/link-config.c | 10 5 + 5 - 0 !
1 file changed, 5 insertions(+), 5 deletions(-)

 make net.ifnames opt-in instead of opt-out

With this commit, you need to actively specify net.ifnames=1 to get
predictable network interface names:
http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/

Also downgrade the "Network interface NamePolicy= disabled on kernel
commandline, ignoring" message to debug, as we expect this to happen right now
and it is confusing.

configure.ac | 14 7 + 7 - 0 !
1 file changed, 7 insertions(+), 7 deletions(-)

 use different default paths for various binaries

Since Debian hasn't done the usr-merge (yet), various binaries are still
installed in / and not /usr.
Update the defaults in configure.ac so we don't have to build-depend on
quota, libcap2-bin, procps, kmod and kexec-tools just to get the correct
paths.  Closes: #721347

src/core/manager.c | 25 25 + 0 - 0 !
1 file changed, 25 insertions(+)

 avoid reloading services when shutting down

Doing so won't work and makes no sense.  Thanks to Michael Stapelberg
for the patch.  Closes: #624599.

src/core/manager.c | 15 15 + 0 - 0 !
1 file changed, 15 insertions(+)

 avoid reload and (re)start requests during early boot which can lead
 to deadlocks

Closes: #624599

units/remote-fs.target | 2 1 + 1 - 0 !
1 file changed, 1 insertion(+), 1 deletion(-)

 order remote-fs.target after local-fs.target

This change was part of the old debianisation branch created by Tollef
and reflects the fact that on Debian the $remote_fs system facility
depends on $local_fs.

rules/99-systemd.rules.in | 12 9 + 3 - 0 !
1 file changed, 9 insertions(+), 3 deletions(-)

 skip 99-systemd.rules when not running systemd as init.

Keep the calling of path_id though, to get consistent ID_PATH attributes under
all init systems. This is required so that tools like systemd-rfkill can be
used with SysVinit or upstart scripts, too.

rules/80-drivers.rules | 1 1 + 0 - 0 !
1 file changed, 1 insertion(+)

 load sg module from 80-drivers.rules

rules/50-udev-default.rules | 14 13 + 1 - 0 !
1 file changed, 13 insertions(+), 1 deletion(-)

 updates to default device permissions

rules/60-persistent-storage.rules | 1 1 + 0 - 0 !
1 file changed, 1 insertion(+)

 set default polling interval on removable devices as well

The events_dfl_poll_msecs rule will not trigger if "block" is not a module, but
built in. This will avoid udisks etc. having to poll from userspace, and
provide proper ejection when the hardware eject button is pressed.

Bug-Debian: https://bugs.debian.org/713877
Bug-Ubuntu: https://launchpad.net/bugs/890592

Makefile.am | 9 9 + 0 - 0 !
src/insserv-generator/Makefile | 28 28 + 0 - 0 !
src/insserv-generator/insserv-generator.c | 326 326 + 0 - 0 !
3 files changed, 363 insertions(+)

 insserv.conf generator

Parse /etc/insserv.conf.d content and /etc/insserv.conf and generate
systemd unit drop-in files to add corresponding dependencies.

This patch is based on work by Frederic Crozat <fcrozat@suse.com>.
See [0] for the original patch.

It has the following modifications:
- it removes support for boot. and bool.localfs which is a SuSE specific
  extension
- it ensures that targets do not start other targets or services
- maps $x-display-manager to display-manager.service, just like the
  sysv-generator

[0] https://build.opensuse.org/package/view_file/openSUSE:Factory/systemd/insserv-generator.patch

Makefile.am | 5 5 + 0 - 0 !
src/sysv-generator/sysv-generator.c | 3 3 + 0 - 0 !
units/mail-transport-agent.target | 12 12 + 0 - 0 !
3 files changed, 20 insertions(+)

 add targets for compatibility with debian insserv system facilities

rules/60-cdrom_id.rules | 8 7 + 1 - 0 !
1 file changed, 7 insertions(+), 1 deletion(-)

 more cd aliases

Add more aliases for CD/DVD devices.

src/login/systemd-user | 5 3 + 2 - 0 !
1 file changed, 3 insertions(+), 2 deletions(-)

 adjust systemd-user pam config file for debian

This pam config file is used by libpam-systemd/systemd-logind when
launching systemd user instances.

src/systemctl/systemctl.c | 17 11 + 6 - 0 !
1 file changed, 11 insertions(+), 6 deletions(-)

 add /run/initctl support to sysv compat tools

sysvinit in Debian uses /run/initctl as FIFO to communicate with PID 1.
Make the SysV compat tools in systemd-sysv try both /run/initctl and the
traditional /dev/initctl. This makes them usable when running sysvinit
as PID 1.

src/shared/sleep-config.c | 6 6 + 0 - 0 !
1 file changed, 6 insertions(+)

 add support for tuxonice hibernation

systemd does not support non-mainline kernel features so upstream rejected this
patch.
It is however required for systemd integration by tuxonice-userui package.

src/sysv-generator/sysv-generator.c | 24 22 + 2 - 0 !
1 file changed, 22 insertions(+), 2 deletions(-)

 add support for rcs.d init scripts to the sysv-generator

src/sysv-generator/sysv-generator.c | 28 27 + 1 - 0 !
1 file changed, 27 insertions(+), 1 deletion(-)

 do not generate systemd units from sysv init scripts if a native
 service file already exists.

man/systemd.special.xml | 9 9 + 0 - 0 !
src/insserv-generator/insserv-generator.c | 2 1 + 1 - 0 !
src/shared/special.h | 2 1 + 1 - 0 !
src/sysv-generator/sysv-generator.c | 7 2 + 5 - 0 !
4 files changed, 13 insertions(+), 7 deletions(-)

 do not order rcs.d services after local-fs.target if they do not
 explicitly depending on $local_fs.

src/sysv-generator/sysv-generator.c | 8 7 + 1 - 0 !
1 file changed, 7 insertions(+), 1 deletion(-)

 map rcs.d init script dependencies to their systemd equivalent.

units/emergency.service.in | 1 1 + 0 - 0 !
1 file changed, 1 insertion(+)

 stop syslog.socket when entering emergency mode

When rsyslog is installed, the syslog.socket is active when entering
emergency mode. This triggers the start of rsyslog.service along with
its dependencies. Since sysinit.target conflicts with emergency.target,
this breaks the emergency mode.
As a workaround, add a Conflicts=syslog.socket to emergency.service to
make sure the socket is stopped when emergency.service is started.

Note: This issue is specific to v208 and is not reproducible with v214,
so this patch should be dropped again when packaging newer releases.

Closes: #755581

src/core/mount-setup.c | 2 2 + 0 - 0 !
1 file changed, 2 insertions(+)

 make /run/lock tmpfs an api fs

The /run/lock directory is world-writable in Debian due to historic
reasons. To avoid user processes filling up /run, we mount a separate
tmpfs for /run/lock. As this directory needs to be available during
early boot, we make it an API fs.

Closes: #751392

src/core/namespace.c | 4 2 + 2 - 0 !
1 file changed, 2 insertions(+), 2 deletions(-)

 include additional directories in protectsystem

man/bootchart.conf.xml | 2 1 + 1 - 0 !
man/sysctl.d.xml | 2 1 + 1 - 0 !
man/systemctl.xml | 4 2 + 2 - 0 !
man/systemd-activate.xml | 6 3 + 3 - 0 !
man/systemd-backlight@.service.xml | 2 1 + 1 - 0 !
man/systemd-binfmt.service.xml | 2 1 + 1 - 0 !
man/systemd-bootchart.xml | 2 1 + 1 - 0 !
man/systemd-bus-proxyd.xml | 2 1 + 1 - 0 !
man/systemd-coredump.xml | 2 1 + 1 - 0 !
man/systemd-cryptsetup-generator.xml | 2 1 + 1 - 0 !
man/systemd-cryptsetup@.service.xml | 2 1 + 1 - 0 !
man/systemd-debug-generator.xml | 2 1 + 1 - 0 !
man/systemd-efi-boot-generator.xml | 2 1 + 1 - 0 !
man/systemd-fsck@.service.xml | 2 1 + 1 - 0 !
man/systemd-fstab-generator.xml | 2 1 + 1 - 0 !
man/systemd-getty-generator.xml | 2 1 + 1 - 0 !
man/systemd-gpt-auto-generator.xml | 2 1 + 1 - 0 !
man/systemd-halt.service.xml | 6 3 + 3 - 0 !
man/systemd-hostnamed.service.xml | 2 1 + 1 - 0 !
man/systemd-initctl.service.xml | 2 1 + 1 - 0 !
man/systemd-journal-gatewayd.service.xml | 2 1 + 1 - 0 !
man/systemd-journald.service.xml | 2 1 + 1 - 0 !
man/systemd-localed.service.xml | 2 1 + 1 - 0 !
man/systemd-logind.service.xml | 2 1 + 1 - 0 !
man/systemd-machined.service.xml | 2 1 + 1 - 0 !
man/systemd-modules-load.service.xml | 2 1 + 1 - 0 !
man/systemd-networkd-wait-online.service.xml | 2 1 + 1 - 0 !
man/systemd-networkd.service.xml | 4 2 + 2 - 0 !
man/systemd-quotacheck.service.xml | 2 1 + 1 - 0 !
man/systemd-random-seed.service.xml | 2 1 + 1 - 0 !
man/systemd-readahead-replay.service.xml | 2 1 + 1 - 0 !
man/systemd-remount-fs.service.xml | 2 1 + 1 - 0 !
man/systemd-resolved.service.xml | 2 1 + 1 - 0 !
man/systemd-rfkill@.service.xml | 2 1 + 1 - 0 !
man/systemd-shutdownd.service.xml | 2 1 + 1 - 0 !
man/systemd-socket-proxyd.xml | 4 2 + 2 - 0 !
man/systemd-suspend.service.xml | 6 3 + 3 - 0 !
man/systemd-sysctl.service.xml | 2 1 + 1 - 0 !
man/systemd-system-update-generator.xml | 2 1 + 1 - 0 !
man/systemd-timedated.service.xml | 2 1 + 1 - 0 !
man/systemd-timesyncd.service.xml | 2 1 + 1 - 0 !
man/systemd-udevd.service.xml | 2 1 + 1 - 0 !
man/systemd-update-done.service.xml | 2 1 + 1 - 0 !
man/systemd-update-utmp.service.xml | 2 1 + 1 - 0 !
man/systemd-user-sessions.service.xml | 2 1 + 1 - 0 !
man/systemd-vconsole-setup.service.xml | 2 1 + 1 - 0 !
man/systemd.directives.xml | 108 54 + 54 - 0 !
man/systemd.link.xml | 6 3 + 3 - 0 !
man/systemd.netdev.xml | 6 3 + 3 - 0 !
man/systemd.network.xml | 6 3 + 3 - 0 !
man/systemd.preset.xml | 6 3 + 3 - 0 !
man/systemd.unit.xml | 4 2 + 2 - 0 !
man/systemd.xml | 2 1 + 1 - 0 !
man/timedatectl.xml | 2 1 + 1 - 0 !
man/udev.xml | 16 8 + 8 - 0 !
55 files changed, 133 insertions(+), 133 deletions(-)

 fix paths in man pages

In Debian we still use the split-/usr setup, where systemd and udev are
installed into / and not /usr.
Fix up the man pages to point at the correct locations.

LP: #1357782
Closes: #717491

configure.ac | 3 1 + 2 - 0 !
1 file changed, 1 insertion(+), 2 deletions(-)

 buildsys: don't default to gold as the linker

systemd fails to build on sparc when using gold as the linker. Since
ifuncs aren't used any more for the compat libraries there isn't a real
reason anymore to explicitely switch to gold as a linker (apart from a
small build speedup). So remove the explict linker selection and use the
default linker instead.

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=760879

src/libsystemd/sd-bus/bus-internal.c | 13 13 + 0 - 0 !
src/libsystemd/sd-bus/bus-internal.h | 1 1 + 0 - 0 !
src/libsystemd/sd-bus/bus-message.c | 4 2 + 2 - 0 !
3 files changed, 16 insertions(+), 2 deletions(-)

 sd-bus: accept :no-sender as the destination field

Revert 51b4ea6f485a85. Older systemd versions (e.g. v208) used
:no-sender as a fallback in direct connections. New systemd doesn't
accept this as a valid sender name and thus causes issues when new
systemctl tries to talk to old systemd.

Should be removed after jessie is released

Closes: #762146

src/login/logind-user.c | 10 9 + 1 - 0 !
1 file changed, 9 insertions(+), 1 deletion(-)

 login: don't overmount /run/user/<uid> on upgrades

Since v215, logind uses a per-user tmpfs for $XDG_RUNTIME_DIR.  When
upgrading from older versions, we don't want to overmount existing user
data, so if that directory already exists, we skip the step where we
mount the per-user tmpfs.

This patch is only necessary for upgrades from pre v215 versions and
should be removed in jessie+1.

Closes: #762041

units/systemd-udevd.service.in | 1 0 + 1 - 0 !
1 file changed, 1 deletion(-)

 udev: re-enable mount propagation for udevd

laptop-mode-tools remounts file systems from within a udev rule to apply
certain mount options. With MountFlags=slave, those mounts then become private
to the systemd-udevd namespace and are no longer accessible from outside the
namespace.
While the root cause is the broken behaviour of laptop-mode-tools, with mount
propagation turned off, this can result in a read-only root file system.
Therefore revert the relevant parts from commit
c2c13f2df42e0691aecabe3979ea81cd7faa35c7 to re-enable mount propagation for
udevd.

Once affected packages have been fixed, this patch should be dropped
again.

Closes: #762018

src/libsystemd/sd-id128/sd-id128.c | 6 5 + 1 - 0 !
1 file changed, 5 insertions(+), 1 deletion(-)

 add env variable for machine id path

During package build, in minimal chroots, or other systems which do not already
have an /etc/machine-id we get six test failures. Introduce a
$SYSTEMD_MACHINE_ID_PATH environment variable which can specify a location
other than /etc/machine-id, so that the unit tests are independent from the
environment.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=62344

Makefile.am | 11 10 + 1 - 0 !
src/default-display-manager-generator/Makefile | 24 24 + 0 - 0 !
src/default-display-manager-generator/default-display-manager-generator.c | 112 112 + 0 - 0 !
3 files changed, 146 insertions(+), 1 deletion(-)

 prefer /etc/x11/default-display-manager if present

Add a generator to ensure /etc/X11/default-display-manager is controlling
which display-manager is started.

src/remount-fs/remount-fs.c | 31 31 + 0 - 0 !
1 file changed, 31 insertions(+)

 fix /usr remount failure for split /usr

Fix systemd-remount-fs.service to not fail on remounting /usr if /usr isn't
mounted yet. This happens with initramfs-tools < 0.118 which we might not get
into Jessie any more.

This can be dropped when /usr always gets mounted from initramfs.

Bug-Debian: https://bugs.debian.org/742048

units/systemd-logind.service.in | 1 1 + 0 - 0 !
1 file changed, 1 insertion(+)

 only start logind if dbus is installed

logind fails to start in environments without dbus, such as LXC containers or
servers. Add a startup condition to avoid the very noisy startup failure.

Part of #772700

src/core/cgroup.c | 2 1 + 1 - 0 !
src/shared/cgroup-util.c | 2 0 + 2 - 0 !
2 files changed, 1 insertion(+), 3 deletions(-)

 cgroup: don't trim cgroup trees created by someone else

In cases when there is a cgroup tree in a controller hierarchy which was
not created by us, but it looks like it was (i.e. cgroup path is the
same as the one in systemd's named hierarchy) we shouldn't delete it.

src/core/execute.c | 10 6 + 4 - 0 !
src/core/execute.h | 1 1 + 0 - 0 !
src/core/unit.c | 4 4 + 0 - 0 !
3 files changed, 11 insertions(+), 4 deletions(-)

 [patch] core: don't fail to run services in --user instances if $home
 is missing

Otherwise we cannot even invoke systemd-exit.service anymore, thus not
even exit.

https://bugs.freedesktop.org/show_bug.cgi?id=83100
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=759320

(cherry picked from commit 4c08c8242a687e00b289e948ccd07b96f0bc4866)

exec: also evaluate working_directory_missing_ok when not applying chroots

(cherry picked from commit cf1d0302aeaf4e44a6a643fb41e5525fdd04b1d5)

src/core/unit.c | 2 1 + 1 - 0 !
1 file changed, 1 insertion(+), 1 deletion(-)

 privatetmp shouldn't require tmpfs

As PrivateTmp is requiring tmp.mount, this one will mount (but only after boot)
/tmp as tmpfs adding a Requires=tmp.mount to the unit. This change downgrades
the requirements to an after relationship.

src/sysv-generator/sysv-generator.c | 57 47 + 10 - 0 !
1 file changed, 47 insertions(+), 10 deletions(-)

 sysv-generator: add support for /etc/insserv/overrides

Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=759001

units/syslog.socket | 3 3 + 0 - 0 !
1 file changed, 3 insertions(+)

 syslog: increase max_dgram_qlen by pulling in
 systemd-setup-dgram-qlen.service

Closes: #762700

src/fstab-generator/fstab-generator.c | 11 8 + 3 - 0 !
units/systemd-fsck-root.service.in | 1 1 + 0 - 0 !
2 files changed, 9 insertions(+), 3 deletions(-)

 skip filesystem check if already done by the initramfs

Newer versions of initramfs-tools already fsck and mount / and /usr in
the initramfs. Skip the filesystem check in this case.

Based on a previous patch by Michael Biebl <biebl@debian.org>.

Closes: #782522
Closes: #810748

src/cryptsetup/cryptsetup.c | 21 19 + 2 - 0 !
1 file changed, 19 insertions(+), 2 deletions(-)

 cryptsetup: implement offset and skip options

These are useful for plain devices as they don't have any metadata by
themselves. Instead of using an unreliable hardcoded device name in crypttab
you can then put static metadata at the start of the partition for a stable
UUID or label.

https://bugs.freedesktop.org/show_bug.cgi?id=87717
https://bugs.debian.org/751707
https://launchpad.net/bugs/953875

src/core/unit.c | 10 1 + 9 - 0 !
1 file changed, 1 insertion(+), 9 deletions(-)

 revert "core: one step back again,
 for nspawn we actually can't wait for cgroups running empty since
 systemd will get exactly zero notifications about it"

This reverts commit 743970d2ea6d08aa7c7bff8220f6b7702f2b1db7.

Bug-Debian: https://bugs.debian.org/784720
Bug-Ubuntu: https://launchpad.net/bugs/1448259
Bug-Fedora: https://bugzilla.redhat.com/show_bug.cgi?id=1141137

src/udev/udevd.c | 2 1 + 1 - 0 !
1 file changed, 1 insertion(+), 1 deletion(-)

 udev: increase udev event timeout to 180s

Some kernel modules, like mptsas, can take longer then 30s to load so
udevd kills the (hanging) worker responsible for loading the module.

Increase timeout from 30s to 180s to workaround this issue, following
the upstream change which first increased the timeout from 30s to 60s
(2e92633) and subsequently to 180s (b5338a1).

Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=787191

src/systemctl/systemctl.c | 38 24 + 14 - 0 !
1 file changed, 24 insertions(+), 14 deletions(-)

 systemctl: add is-enabled support for sysv init scripts

The update-rc.d utility does not provide is-enabled, so implement it
ourselves in systemctl using the same logic as systemd-sysv-install from
Stretch.
See commit b5aa768d8108b294c1187a0728f5b13c033b3d47

Closes: #809405