Grafana-server: unrecognized service

Grafana Configuration
1

Hi, i have installed hawkular-datasource plugin on my grafana.

I cant run : service grafana-server restart

this is all step:

grafana@grafana-5-7gf7w:/$ grafana-cli plugins ls
installed plugins:
hawkular-datasource @ 1.1.1

Restart grafana after installing plugins .

grafana@grafana-5-7gf7w:/$ service grafana-server restart
grafana-server: unrecognized service

hint form me?

thansk for support.