2.5 动态配置采集目标

配置采集目标 targets:

• static_configs: 直接在配置文件中指定 targets
• file_sd_configs: 通过 json 文件指定 targets
• consul_sd_configs: 通过 consul 服务指定 targets

基于文件

通过 targets.json 文件定义所有的监控目标：

[
  {
    "targets": [ "localhost:8080"],
    "labels": {
      "env": "localhost",
      "job": "cadvisor"
    }
  },
  {
    "targets": [ "localhost:9104" ],
    "labels": {
      "env": "prod",
      "job": "mysqld"
    }
  },
  {
    "targets": [ "localhost:9100"],
    "labels": {
      "env": "prod",
      "job": "node"
    }
  }
]

创建 prometheus 配置文件：

global:
  scrape_interval: 15s
  scrape_timeout: 10s
  evaluation_interval: 15s
scrape_configs:
  - job_name: 'file_ds'
    file_sd_configs:
      - refresh_interval: 1m
        files:
          - targets.json

prometheus 周期性读取文件中的内容，当文件中定义的内容发生变化时，不需要对 prometheus 进行重启

Consul

下载(https://www.consul.io/downloads.html)

$ wget https://releases.hashicorp.com/consul/1.4.4/consul_1.4.4_linux_amd64.zip
$ unzip consul_1.4.4_linux_amd64.zip

启动（开发者模式，单节点）

$ ./consul agent -dev

查看集群节点：

$ ./consul members

$ curl localhost:8500/v1/catalog/nodes

添加服务：

$ echo '{"service": {"name": "node_exporter", "tags": ["exporter"], "port": 9100}}' \
    | sudo tee /etc/consul.d/node_exporter.json

$ consul agent -dev -config-dir=/etc/consul.d

$ curl http://localhost:8500/v1/catalog/service/node_exporter

通过 put 请求添加服务：

$ curl http://localhost:8900/v1/agent/service/register -X PUT -i -H "Content-Type:application/json" -d '{
   "ID": "kafkaNode3",
   "Name": "kafkaNode",
   "Tags": [
     "node"
   ],
   "Address": "10.9.145.115",
   "Port": 5556,
   "EnableTagOverride": false,
   "Check": {
     "DeregisterCriticalServiceAfter": "90m",
     "HTTP": "http://10.9.164.4:65431?Action=CheckHealth",
     "Interval": "10s"
   }
  }'

$ curl http://localhost:8500/v1/catalog/services

$ curl http://localhost:8500/v1/catalog/service/kafkaNode

在consul_sd_configs定义当中通过server定义了Consul服务的访问地址，services则定义了当前需要发现哪些类型服务实例的信息，这里限定了只获取node_exporter的服务实例信息。

- job_name: node_exporter
    metrics_path: /metrics
    scheme: http
    consul_sd_configs:
      - server: localhost:8500
        services:
          - node_exporter