Unit nagios.service not found

[KillSwitch00110]

I ran into a weird issue this morning, one I have never encountered. When I log into the web interface I get Nagios Core Not running. I checked the services, see the output below.

/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg

Nagios Core 4.3.1
Copyright (c) 2009-present Nagios Core Development Team and Community Contributors
Copyright (c) 1999-2009 Ethan Galstad
Last Modified: 02-23-2017
License: GPL

Website: https://www.nagios.org
Reading configuration data...
Read main config file okay...
Read object config files okay...

Running pre-flight check on configuration data...

Checking objects...
Checked 8 services.
Checked 1 hosts.
Checked 1 host groups.
Checked 0 service groups.
Checked 1 contacts.
Checked 1 contact groups.
Checked 24 commands.
Checked 5 time periods.
Checked 0 host escalations.
Checked 0 service escalations.
Checking for circular paths...
Checked 1 hosts
Checked 0 service dependencies
Checked 0 host dependencies
Checked 5 timeperiods
Checking global event handlers...
Checking obsessive compulsive processor commands...
Checking misc settings...

Total Warnings: 0
Total Errors: 0

Things look okay - No serious problems were detected during the pre-flight check

But when I try to restart the service I get this.

:/tmp/nagios-4.3.1# service nagios restart
Failed to restart nagios.service: Unit nagios.service not found.

cd /root/nagios
bash: cd: /root/nagios: No such file or directory

I have installed Nagios numerous times and have never had this issue. I am running this installation on Ubuntu 16.10. Any help with this weird issue would be greatly appreciated.

[KillSwitch00110]

Never Mind I figured out my own mistake. Something stupid I over looked.

I fixed it by doing /etc/init.d/nagios start.

service nagios start

[dwhitfield]

No problem. I'll lock this up!