autostart - Service (grafana-server) does not start automatically on Ubuntu 16.04

I have a problem with autostarting Grafana on Ubuntu 16.04 (while it starts automatically on 14.04, also other added services on 16.04 configured in a similar way do start automatically).

I ran configuration as below:

$ sudo update-rc.d grafana-server defaults

No output from the command (running multiple times does not print any new information):

$ sudo update-rc.d grafana-server defaults
$ sudo update-rc.d grafana-server defaults
$
$ sudo reboot

After restart the service is stopped (if I delete /var/log/grafana/grafana.log before reboot, it is not created). The status is:

$ sudo service grafana-server status
● grafana-server.service - Starts and stops a single grafana instance on this system
   Loaded: loaded (/usr/lib/systemd/system/grafana-server.service; disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: http://docs.grafana.org

And the service starts up when called manually:

$ sudo service grafana-server status
● grafana-server.service - Starts and stops a single grafana instance on this system
   Loaded: loaded (/usr/lib/systemd/system/grafana-server.service; disabled; vendor preset: enabled)
   Active: active (running) since Sun 2016-07-17 23:07:33 JST; 1s ago
     Docs: http://docs.grafana.org
 Main PID: 2658 (grafana-server)
    Tasks: 7 (limit: 512)
   Memory: 23.0M
      CPU: 105ms
   CGroup: /system.slice/grafana-server.service

           └─2658 /usr/sbin/grafana-server --config=/etc/grafana/grafana.ini --pidfile= cfg:default.paths.logs=/var/log/grafana cfg:de

After another reboot, it does not start.

Startup scripts in init.d are present:

$ ls -l /etc/rc3.d/*grafana*
lrwxrwxrwx 1 root 24 Jul 17 22:58 /etc/rc3.d/S04grafana-server -> ../init.d/grafana-server*
$ ls -l /etc/init.d/grafana-server

-rwxr-xr-x 1 root 3291 Jul 12 19:57 /etc/init.d/grafana-server*

What might be wrong?