用prometheus监控Nginx

GitHub上官方地址：https://github.com/knyar/nginx-lua-prometheus
告警规则地址：https://awesome-prometheus-alerts.grep.to/rules#nginx

1.nginx需要支持lua功能，若是使用openresty的话，则自带支持lua
2.把lua文件上传到服务器中，
3.修改nginx配置文件，加载lua功能

# cat nginx.conf
http {

  ......

  lua_shared_dict prometheus_metrics 10M;
  lua_package_path "/path/to/nginx-lua-prometheus/?.lua;;"; # lua文件存放路径
  init_worker_by_lua_block {
    prometheus = require("prometheus").init("prometheus_metrics")
    metric_requests = prometheus:counter(
      "nginx_http_requests_total", "Number of HTTP requests", {"host", "status"})
    metric_latency = prometheus:histogram(
      "nginx_http_request_duration_seconds", "HTTP request latency", {"host"})
    metric_connections = prometheus:gauge(
      "nginx_http_connections", "Number of HTTP connections", {"state"})
  }
  log_by_lua_block {
    metric_requests:inc(1, {ngx.var.server_name, ngx.var.status})
    metric_latency:observe(tonumber(ngx.var.request_time), {ngx.var.server_name})
  }

  server {

    ......
    # 设置prometheus收集收据接口
    location /metrics {
      content_by_lua_block {
        metric_connections:set(ngx.var.connections_reading, {"reading"})
        metric_connections:set(ngx.var.connections_waiting, {"waiting"})
        metric_connections:set(ngx.var.connections_writing, {"writing"})
        prometheus:collect()
      }
    }
  }

}

4.先检测nginx配置文件，然后重启nginx，访问 http://ip:port/metrics
5.修改prometheus配置文件，加上监听nginx的配置

  - job_name: 'nginx'
    static_configs:
    - targets: ['localhost:80']

6.把nginx告警规则放在prometheus指定目录下

重启prometheus

7.grafana使用的模板
模板ID：10223
地址：https://grafana.com/grafana/dashboards/10223

另一种方式，参考网址：https://www.cnblogs.com/you-men/p/13173245.html