案例：用marathon-lb 绑定tomcat端口，并自动服务发现与负载均衡。

部署marathon-lb

在marathon上部署marathon-lb
访问marathon ui 地址： http://192.168.22.191:8080
创建应用-选择json模式-拷贝下面的内容

{
  "id": "/marathon-lb",
  "cmd": "apt-get install curl -y && /marathon-lb/run sse --marathon http://192.168.22.191:8080 --group external",
  #设置HAPROXY_GROUP标签为 external
  "cpus": 1,
  "mem": 128,
  "disk": 0,
  "instances": 1,
  "constraints": [
    [
      "hostname",
      "LIKE",
      "192.168.22.192"   #指定部署的节点
    ]
  ],
  "acceptedResourceRoles": [
    "*"
  ],
  "container": {
    "type": "DOCKER",
    "docker": {
      "forcePullImage": false,
      "image": "docker.io/mesosphere/marathon-lb",
       #需执行docker pull mesosphere/marathon-lb命令下载镜像
      "parameters": [],
      "privileged": true
    },
    "volumes": []
  },
  "portDefinitions": [
    {
      "port": 10001,
      "name": "default",
      "protocol": "tcp"
    }
  ]
}

部署成功的状态

image.png

部署tomcat

marathon上部署tomcat
json内容：

{
  "id": "/test-tomcat",
  "cmd": null,
  "cpus": 0.5,
  "mem": 128,
  "disk": 0,
  "instances": 2,
  #启动容器的数量
  "acceptedResourceRoles": [
    "*"
  ],
  "container": {
    "type": "DOCKER",
    "docker": {
      "forcePullImage": false,
      "image": "tomcat:8.5.32",
      #提前执行docker pull tomcat:8.5.32命令下载镜像
      "parameters": [],
      "privileged": false
    },
    "volumes": [
      {
        "containerPath": "/usr/local/tomcat/logs",    #容器里的目录
        "hostPath": "/opt/test-tomcat",    #主机的目录
        "mode": "RW"   #权限
        #日志目录映射
      }
    ],
    "portMappings": [
      {
        "containerPort": 8080,    #容器里的tomcat端口
        "hostPort": 0,                  #主机的端口0表示随机
        "labels": {},          
        "protocol": "tcp",
        "servicePort": 10001     #服务端口
      }
    ]
  },
  "healthChecks": [
    {
      "gracePeriodSeconds": 300,
      "ignoreHttp1xx": false,
      "intervalSeconds": 10,
      "maxConsecutiveFailures": 3,
      "path": "/",
      "portIndex": 0,
      "protocol": "HTTP",
      "ipProtocol": "IPv4",
      "timeoutSeconds": 20,
      "delaySeconds": 15
    }
  ],
  "labels": {
    "HAPROXY_GROUP": "external",      
    #设置HAPROXY_GROUP标签，需与marathon-lb一致
    "HAPROXY_0_VHOST": "tomcat.marathon.mesos",
    "HAPROXY_DEPLOYMENT_ALT_PORT": "10002"
  },
  "networks": [
    {
      "mode": "container/bridge"
    }
  ],
  "portDefinitions": []
}

部署成功后的状态

image.png

分别访问tomcat地址验证
http://192.168.22.193:27643
http://192.168.22.193:24308

image.png

image.png

查看marathon-lb状态

访问marathon-lb获取HAProxy的统计信息 http://192.168.22.192:9090/haproxy?stats

image.png

访问marathon-lb负载后的地址

http://192.168.22.192:10001

image.png

重启tomcat验证marathon-lb服务发现

重启tomcat后再访问以下两个地址观察
http://192.168.22.192:9090/haproxy?stats
http://192.168.22.192:10001