Prometheus/node_exporter : install & configure systemd

1. Create user and directory

- user/group name : node_exporter

$ useradd --no-create-home --shell /bin/false node_exporter

$ cat /etc/passwd | grep node_exporter
node_exporter:x:1001:1001::/home/node_exporter:/bin/false

$ grep node_exporter /etc/group
node_exporter:x:1001:

2. Installing node_exporter install and creating config file/directory

- download node_exporter from https://prometheus.io/download/

$ tar zxvf node_exporter-1.6.0.linux-amd64.tar.gz
$ cd node_exporter-1.6.0.linux-amd64/
$ cp node_exporter /usr/sbin

$ touch touch /etc/sysconfig/node_exporter
$ mkdir -p /var/lib/node_exporter/textfile_collector/

3. Change ownership

$ chown node_exporter:node_exporter /usr/sbin/node_exporter
$ chown node_exporter:node_exporter /etc/sysconfig/node_exporter
$ chown node_exporter:node_exporter /var/lib/node_exporter
$ chown node_exporter:node_exporter /var/lib/node_exporter/textfile_collector

4. Creating systemd config

- systemd config

$ vi /etc/systemd/system/prometheus.service
[Unit]
Description=Node Exporter

[Service]
User=node_exporter
EnvironmentFile=/etc/sysconfig/node_exporter
ExecStart=/usr/sbin/node_exporter $OPTIONS

[Install]
WantedBy=multi-user.target

- environment config (ex OPTIONS)

$ vi /etc/sysconfig/node_exporter
OPTIONS="--collector.textfile.directory /var/lib/node_exporter/textfile_collector"

5. Enable/start service

$systemctl daemon-reload

$ systemctl enable node_exporter
Created symlink /etc/systemd/system/multi-user.target.wants/node_exporter.service → /etc/systemd/system/node_exporter.service.

$ systemctl start node_exporter

$ systemctl status node_exporter
● node_exporter.service - Node Exporter
   Loaded: loaded (/etc/systemd/system/node_exporter.service; enabled; vendor preset: disabled)
   Active: active (running) since Fri 2023-06-30 09:05:39 KST; 5s ago
 Main PID: 3875 (node_exporter)
    Tasks: 6 (limit: 50220)
   Memory: 5.2M
   CGroup: /system.slice/node_exporter.service
           └─3875 /usr/sbin/node_exporter --collector.textfile.directory /var/lib/node_exporter/textfile_collector

Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=thermal_zone
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=time
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=timex
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=udp_queues
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=uname
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=vmstat
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=xfs
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.869Z caller=node_exporter.go:117 level=info collector=zfs
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.870Z caller=tls_config.go:274 level=info msg="Listening on" address=[::]:9100
Jun 30 09:05:39 nodeExporter node_exporter[3875]: ts=2023-06-30T00:05:39.870Z caller=tls_config.go:277 level=info msg="TLS is disabled." http2=false address=[::]>