[systemd-devel] Spurious failures starting ConnMan with systemd

[Daniel Wagner]

Hi Colin,

On 11/15/2016 03:46 PM, Colin Guthrie wrote:
> Hope you're keeping well?

Doing fine! How is live in the north? 
 
> So, by default, dbus should be socket activated. That means that when
> dbus.service eventually starts shouldn't really matter, provided it is
> eventually started. This is because it's actually dbus.socket that's the
> important unit. It should be started by sockets.target which is pulled
> in as part of the default dependencies that all units get automatically
> (provided they've not disabled this)

Okay, that makes sense.

> So, check for dbus.socket, and check that connman.service doesn't
> disable default deps.

I think we do, see below.

> If socket activation is used, then there shouldn't be any need to
> mention dbus.socket/service in connman.service at all.

"""
[Unit]
Description=Connection service
DefaultDependencies=false
Conflicts=shutdown.target
RequiresMountsFor=/var/lib/connman
After=dbus.service network-pre.target systemd-sysusers.service
Before=network.target multi-user.target shutdown.target
Wants=network.target

[Service]
Type=dbus
BusName=net.connman
Restart=on-failure
ExecStart=/usr/sbin/connmand -n
StandardOutput=null
CapabilityBoundingSet=CAP_KILL CAP_NET_ADMIN CAP_NET_BIND_SERVICE CAP_NET_RAW CAP_SYS_TIME CAP_SYS_MODULE
ProtectHome=true
ProtectSystem=full

[Install]
WantedBy=multi-user.target
"""

Okay, so the DefaultDependencies=false is causing this problem then.
In our commit history I found following explanation for it:

"""
commit 09aa0243aac40ec4e5bd0fbe41e702be4952a382
Author: Patrik Flykt <patrik.flykt at linux.intel.com>
Date:   Thu Sep 17 10:42:46 2015 +0300

    connman.service: Fix dependencies for early boot
    
    Unset default dependencies in order to properly run at early boot and
    require the save directory to be mounted before starting.
    
    See the systemd.unit man page, Debian's wiki page
    https://wiki.debian.org/Teams/pkg-systemd/rcSMigration and the upstream
    systemd-networkd.service file for details.

diff --git a/src/connman.service.in b/src/connman.service.in
index 8f7f3429f7dc..0a8f15c9f90b 100644
--- a/src/connman.service.in
+++ b/src/connman.service.in
@@ -1,7 +1,10 @@
 [Unit]
 Description=Connection service
+DefaultDependencies=false
+Conflicts=shutdown.target
+RequiresMountsFor=@localstatedir@/lib/connman
 After=dbus.service network-pre.target
-Before=network.target remote-fs-pre.target
+Before=network.target shutdown.target remote-fs-pre.target
 Wants=network.target remote-fs-pre.target
 
 [Service]
"""

Hmm, now I am confused...

Thanks,
Daniel