[terraform] install prometheus node-exporter - ec2 user data

modules/terraform-aws-alternat/main.tf

@@ -174,6 +174,10 @@ data "cloudinit_config" "config" {
 
   gzip          = true
   base64_encode = true
+  part {
+    content_type = "text/x-shellscript"
+    content      = file("${path.module}/../../scripts/node-exporter.sh")
+  }
   part {
     content_type = "text/x-shellscript"
     content = templatefile("${path.module}/alternat.conf.tftpl", {

scripts/node-exporter.sh

@@ -0,0 +1,77 @@
+#!/bin/bash
+
+# ABOUT: this script installs the prometheus-node-exporter
+# as a systemd service on the system
+
+export SERVICE_USER="node_exporter"
+export CONFIG_DIR="/etc/node-exporter"
+export VERSION="1.6.1"
+
+# download and install binary
+
+mkdir /tmp/download
+cd /tmp/download
+wget "https://github.com/prometheus/node_exporter/releases/download/v${VERSION}/node_exporter-${VERSION}.linux-amd64.tar.gz"
+tar xzf node_exporter-${VERSION}.linux-amd64.tar.gz
+cp node_exporter-${VERSION}.linux-amd64/node_exporter /usr/local/sbin/
+
+# create service user and group
+
+adduser --system --no-create-home --group ${SERVICE_USER}
+
+# create config
+
+mkdir ${CONFIG_DIR}
+
+cat >${CONFIG_DIR}/node_exporter_env <<EOL
+OPTIONS="--collector.textfile.directory /var/lib/node_exporter/textfile_collector --collector.tcpstat --collector.systemd --collector.filesystem.ignored-mount-points=^/(sys|proc|dev|run)($|/)"
+EOL
+
+chown -R ${SERVICE_USER}:${SERVICE_USER} ${CONFIG_DIR}
+chmod 0644 ${CONFIG_DIR}/node_exporter_env
+
+# create data dir
+
+mkdir -p /var/lib/node_exporter/textfile_collector
+chown -R ${SERVICE_USER}:${SERVICE_USER} /var/lib/node_exporter
+
+# create service dependency - socket
+
+cat >/etc/systemd/system/node_exporter.socket <<EOL
+[Unit]
+Description=Node Exporter
+
+[Socket]
+ListenStream=9100
+
+[Install]
+WantedBy=sockets.target
+EOL
+
+chown root:root /etc/systemd/system/node_exporter.socket
+chmod 0644 /etc/systemd/system/node_exporter.socket
+
+# create systemd service unit
+
+cat >/etc/systemd/system/node_exporter.service <<EOL
+[Unit]
+Description=Node Exporter
+Requires=node_exporter.socket
+
+[Service]
+User=node_exporter
+EnvironmentFile=/etc/node-exporter/node_exporter_env
+ExecStart=/usr/local/sbin/node_exporter --web.systemd-socket $OPTIONS
+
+[Install]
+WantedBy=multi-user.target
+EOL
+
+chown root:root /etc/systemd/system/node_exporter.service
+chmod 0644 /etc/systemd/system/node_exporter.service
+
+# enable and start systemd service
+
+systemctl daemon-reload
+systemctl enable node_exporter.service
+systemctl start node_exporter.service