node-exporter install (dedicated user, no package)

See the latest version, and correct CPU architecture over at
https://github.com/prometheus/node_exporter/releases/latest

# grab latest release EXAMPLE:
# wget https://github.com/prometheus/node_exporter/releases/download/v1.10.2/node_exporter-1.10.2.linux-amd64.tar.gz
tar -xf node_exporter-1.10.2.linux-amd64.tar.gz
cd node_exporter-1.10.2.linux-amd64/
ls
./node_exporter # see if it works

sudo groupadd --system node_exporter
sudo useradd -s /sbin/nologin --system -g node_exporter node_exporter
sudo cp node_exporter /usr/bin/
sudo chown node_exporter:node_exporter /usr/bin/node_exporter
nano /usr/lib/systemd/system/node_exporter.service

you can use either
/usr/lib/systemd/system/
/etc/systemd/system/
but i'll go with
/usr/lib/systemd/system/node_exporter.service

[Unit]
Description=Node Exporter
Documentation=https://prometheus.io/docs/guides/node-exporter/
Wants=network-online.target
After=network-online.target

[Service]
User=node_exporter
Group=node_exporter
Type=simple
Restart=on-failure
ExecStart=/usr/bin/node_exporter

[Install]
WantedBy=multi-user.target

sudo chmod 664 /usr/lib/systemd/system/node_exporter.service
sudo systemctl daemon-reload
sudo systemctl enable node_exporter
sudo systemctl start node_exporter

see http://<host>:9100/metrics