# prometheus 安裝

步驟
---
- 安裝 wget
- 下載 prometheus
- 解壓縮 prometheus
- 啟動 prometheus
- 安裝並啟動Node Exporter
- 設定監控相關參數，並重新啟動prometheus

相關設定與檔案
---
## prometheus.yml(主要設定檔)
### rule_files
用於指定哪一個檔案設定通報監控機制
### scrape_configs設定configs
透過job_name指定相關設定類型
#### prometheus(本身設定參數)
targets 該監控主機IP
#### node_exporter_metrics(受監控者相關設定)
targets 受監控主機IP

# Alertmanager configuration
alerting:
  alertmanagers:
    - static_configs:
        - targets:
          # - alertmanager:9093

# Load rules once and periodically evaluate them according to the global 'evaluation_interval'.
rule_files:
  - "alert_rules.yml"
  # - "first_rules.yml"
  # - "second_rules.yml"

# A scrape configuration containing exactly one endpoint to scrape:
# Here it's Prometheus itself.
scrape_configs:
  # The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
  - job_name: "prometheus"

    # metrics_path defaults to '/metrics'
    # scheme defaults to 'http'.

    static_configs:
      - targets: ["your_ip:9090"]
  - job_name: 'node_exporter_metrics'
    scrape_interval: 5s
    static_configs:
      - targets: ['your_ip:9100']

## alert_rules.yml(監控設定檔)

groups:
- name: cpu_alerts
  rules:
  - alert: HighCPUUsage
    expr: (1 - rate(node_cpu_seconds_total{mode="idle"}[5m])) * 100 > 80
    for: 2m
    labels:
      severity: critical
      instance: "{{ $labels.instance }}"
    annotations:
      summary: "High CPU Usage Detected"
      description: "CPU usage on {{ $labels.instance }} is above 90"

- name: memory_alerts
  rules:
  - alert: HighMemoryUsage
    expr: ((node_memory_MemTotal_bytes - node_memory_MemFree_bytes - node_memory_Cached_bytes) / node_memory_MemTotal_bytes) * 100 > 80
    for: 2m
    labels:
      severity: critical
      instance: "{{ $labels.instance }}"
    annotations:
      summary: "High Memory Usage Detected"
      description: "Memory usage on {{ $labels.instance }} is above 90%"

- name: disk_alerts
  rules:
  - alert: DiskSpaceAlert
    expr: (node_filesystem_free_bytes{mountpoint="/"} / node_filesystem_size_bytes{mountpoint="/"} * 100) < 10
    for: 5m
    labels:
      severity: critical
      instance: "{{ $labels.instance }}"
    annotations:
      summary: "Disk Space Usage High"
      description: "Disk space on {{ $labels.instance }} is running low."

參考
---
- [安裝wget](https://www.delftstack.com/zh-tw/howto/linux/how-to-use-wget-command-in-linux/#%25E6%25AA%25A2%25E6%259F%25A5-linux-%25E6%2598%25AF%25E5%2590%25A6%25E5%25AE%2589%25E8%25A3%259D%25E4%25BA%2586-wget)
- [安裝prometheus](https://ryanisagoodguy.blogspot.com/2019/12/centosprometheusgrafana.html)
- [prometheus 官方文件](https://prometheus.io/download/)
- [輕鬆管理 Metrics 的工具，Prometheus 介紹](https://ithelp.ithome.com.tw/articles/10299053)
- https://ithelp.ithome.com.tw/articles/10336643
- https://hackmd.io/@gdsc-ntcu/r1fBFO0Pa
- https://ken00535.medium.com/use-prometheus-to-monitor-end-devices-bec0712b1d5
- https://hackmd.io/@cheese-owner/BkF8Kmlc5?utm_source=preview-mode&utm_medium=rec

###### tags: `Templates` `Book`