prometheus-node-exporter does not start on ubuntu 14.04

[yctn]

i changed the init file to the following. then it started again.

`description "Prometheus Node Exporter"
start on runlevel [2345]

respawn
setuid prometheus
setgid prometheus

script
exec >> "/var/log/prometheus/node-exporter.log"
exec 2>&1
exec /opt/prometheus/exporters/node_exporter_current/node_exporter --collector.conntrack --collector.cpu --collector.diskstats --collector.entropy --collector.filefd --collector.filesystem --collector.loadavg --collector.meminfo --collector.netdev --collector.netstat --collector.stat --collector.textfile --collector.time --collector.vmstat --collector.textfile.directory=/var/log/prometheus/textfile_collector --web.listen-address=0.0.0.0:9100 --log.level=info
end script
`