[lttng-dev] lttng-sessiond as a CentOS 7 service

[Thibault, Daniel]

Using:
lttng-modules-stable-2.8-2.8.2-e840206
userspace-rcu-stable-0.9-6051170
lttng-ust-stable-2.8-cf18865
lttng-tools-stable-2.8-2.8.2-48262f1
on:
Red Hat Enterprise Linux Server release 7.2 (Maipo) (RHEL 7.2 64-bits)
Kernel 3.10.0-327.el7.x86_64

I'm having trouble with my installation of lttng-sessiond as a service.  If I run lttng-sessiond using either -b, -d, or just -vvv, it works fine (I can interrogate 'lttng list -u' from a tracing user shell and detect the process using 'ps -e | grep sessiond').

But when I launch the service, I end up with a "successfully dead" daemon:

# systemctl start lttng-sessiond
# systemctl status lttng-sessiond
* lttng-sessiond.service - LTTng central tracing registry session daemon
   Loaded: loaded (/etc/systemd/system/lttng-sessiond.service; enabled; vendor preset: enabled)
   Active: inactive (dead) since ...
  Process: 5865 ExecStart=/usr/local/bin/lttng-sessiond -d (code=exited, status=0/SUCCESS)
 Main PID: 5865 (code=exited, status=0/SUCCESS)

There's nothing in dmesg.

The service is set up like so:

$ sudo ln -s /etc/systemd/system/lttng-sessiond.service /etc/systemd/system/multi-user.target.wants/lttng-sessiond.service
$ cat > ~/lttng-sessiond.service << END
[Unit]
Description=LTTng central tracing registry session daemon

[Service]
Type=simple
User=root
ExecStart=/usr/local/bin/lttng-sessiond -d
Restart=on-abort

[Install]
WantedBy=multi-user.target
END
$ sudo mv ~/lttng-sessiond.service /etc/systemd/system/lttng-sessiond.service

What am I doing wrong?

Daniel U. Thibault, M.Sc.²

Informaticien scientifique, CME-PSC, Centre de recherches de Valcartier
Recherche et développement pour la défense Canada / Gouvernement du Canada
daniel.thibault at drdc-rddc.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538
daniel.thibault at forces.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538

Computer Scientist, MCCS-SPC, Valcartier Research Centre 
Defence Research and Development Canada / Government of Canada
daniel.thibault at drdc-rddc.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538
daniel.thibault at forces.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538

DRDC is an agency of the Department of National Defence / RDDC est une agence du ministère de la Défense nationale