前提

Docker

前言

现在Docker Swarm已经彻底输给了K8S,但是现在K8S依然很复杂，上手难度较Docker Swarm高，如果是小规模团队且需要容器编排的话，使用Docker Swarm还是适合的。

目前Docker Swarm有一个问题一直没有解决，如果业务需要知道用户的请求IP,则Docker Swarm满足不了要求。目前部署在Docker Swarm内的服务,无法获取到用户的请求IP。

具体可以看看这个ISSUE->Unable to retrieve user's IP address in docker swarm mode

整体思路

思路整体来说是使用Influxdb+Grafana+cadvisor,其中cadvisor负责数据的收集，每一台节点都部署一个cadvisor服务,Influxdb负责数据的存储,Grafana负责数据的可视化。

/img/bVxJw

演示环境

主机	IP
master(manager)	192.168.1.60
node1(worker)	192.168.1.61
node2(worker)	192.168.1.62

/img/bVxJx

我这里是将master节点当作监控数据存储以及可视化服务的节点作为演示,一般是拿一个worker节点做这样的工作。

初始化Docker Swarm

在master机器上初始化集群,运行
docker swarm init --advertise-addr {MASTER-IP}

[root@master ~]# docker swarm init --advertise-addr 192.168.1.60

Swarm initialized: current node (138n5rwjz83y8goyzepp1cdo7) is now a manager.

To add a worker to this swarm, run the following command:

    docker swarm join --token SWMTKN-1-67je7chylnpyt0s4k1ee63rhxgh0qijiah9gadvcr7i6uab909-535nf6qu6v7b8dscc0plghr9j 192.168.1.60:2377

To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions

在node节点运行提示的命令加入到集群中
``
docker swarm join --token SWMTKN-1-67je7chylnpyt0s4k1ee63rhxgh0qijiah9gadvcr7i6uab909-535nf6qu6v7b8dscc0plghr9j 192.168.1.60:2377
``
manager节点初始化集群后，都会有这样一个提示，这个的命令只是给个示例，实际命令需要根据初始化集群后的真实情况来运行。

[root@node1 ~]#  docker swarm join --token SWMTKN-1-67je7chylnpyt0s4k1ee63rhxgh0qijiah9gadvcr7i6uab909-535nf6qu6v7b8dscc0plghr9j 192.168.1.60:2377
This node joined a swarm as a worker.

[root@node2 ~]#  docker swarm join --token SWMTKN-1-67je7chylnpyt0s4k1ee63rhxgh0qijiah9gadvcr7i6uab909-535nf6qu6v7b8dscc0plghr9j 192.168.1.60:2377
This node joined a swarm as a worker.

在master机器上查看当前的node节点

``
docker node ls
``

[root@master ~]# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
138n5rwjz83y8goyzepp1cdo7 *   master              Ready               Active              Leader              18.09.8
q03by75rqur63lx36cmordf11     node1               Ready               Active                                  18.09.8
6shdf5ej4b5u7x877bg9nyjk3     node2               Ready               Active

到目前为止集群已经搭建完成了，接下来开始部署服务

在Docker Swarm部署监控服务

``
docker stack deploy -c docker-compose-monitor.yml monitor
``

[root@master ~]# docker stack deploy -c docker-compose-monitor.yml monitor
Creating network monitor_default
Creating service monitor_influx
Creating service monitor_grafana
Creating service monitor_cadvisor

docker-compose-monitor.yml文件内容

version: '3'

services:
 influx:
   image: influxdb
   volumes:
     - influx:/var/lib/influxdb
   deploy:
     replicas: 1
     placement:
       constraints:
         - node.role == manager

 grafana:
   image: grafana/grafana
   ports:
     - 0.0.0.0:80:3000
   volumes:
     - grafana:/var/lib/grafana
   depends_on:
     - influx
   deploy:
     replicas: 1
     placement:
       constraints:
         - node.role == manager

 cadvisor:
   image: google/cadvisor
   hostname: '{{.Node.Hostname}}'
   command: -logtostderr -docker_only -storage_driver=influxdb -storage_driver_db=cadvisor -storage_driver_host=influx:8086
   volumes:
     - /:/rootfs:ro
     - /var/run:/var/run:rw
     - /sys:/sys:ro
     - /var/lib/docker/:/var/lib/docker:ro
   depends_on:
     - influx
   deploy:
     mode: global

volumes:
 influx:
   driver: local
 grafana:
   driver: local

下载docker-compose-monitor.yml

查看服务的部署情况

``
docker service ls
``

[root@master ~]# docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE                    PORTS
qth4tssf2sm1        monitor_cadvisor    global              3/3                 google/cadvisor:latest   
p2vbxe7ic175        monitor_grafana     replicated          1/1                 grafana/grafana:latest   *:80->3000/tcp
von1rpeqq7vj        monitor_influx      replicated          1/1                 influxdb:latest

到目前为止，服务已经部署完成了，三台机器各自部署一个cadvisor,在master节点部署了grafana和influxdb

为cadvisor配置influxdb数据库

查看一下master机器上的服务
``
docker ps
``

[root@master ~]# docker ps
CONTAINER ID        IMAGE                    COMMAND                  CREATED             STATUS              PORTS               NAMES
55965fdf13a3        grafana/grafana:latest   "/run.sh"                3 hours ago         Up 3 hours          3000/tcp            monitor_grafana.1.l9uh0ov7ltk7q2yollmk4x1v9
0bf544c7d81c        google/cadvisor:latest   "/usr/bin/cadvisor -…"   3 hours ago         Up 3 hours          8080/tcp            monitor_cadvisor.138n5rwjz83y8goyzepp1cdo7.l53vufoivp0oe8tyy14nh0jof
3ce050f0483e        influxdb:latest          "/entrypoint.sh infl…"   3 hours ago         Up 3 hours          8086/tcp            monitor_influx.1.vraeh8ektium1j1jd27qvq1au
[root@master ~]#

可以看到是符合预期的，接下来进一步查看cadvisor容器的日志
``
docker logs -f 0bf544c7d81c
``

[root@master ~]# docker logs -f 0bf544c7d81c
W0209 09:32:15.730951       1 manager.go:349] Could not configure a source for OOM detection, disabling OOM events: open /dev/kmsg: no such file or directory
E0209 09:33:15.783705       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:34:15.818661       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:35:16.009312       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:36:16.027113       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:37:16.107051       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:38:16.215684       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}
E0209 09:39:16.305772       1 memory.go:94] failed to write stats to influxDb - {"error":"database not found: \"cadvisor\""}

可以看到现在一直是在报错的，因为目前的influx容器中没有cadvisor这样的数据库存在，接下来我们进入influx容器并创建对应的cadvisor数据库,在master机器上执行以下命令即可。

``
docker exec docker ps | grep -i influx | awk '{print $1}' influx -execute 'CREATE DATABASE cadvisor'
``

当然，也可以分步骤执行

找到influxdb的容器
进入到influxdb容器内并登陆influx
创建数据库

这里就不演示了。

配置grafana

到目前为止，数据已经在收集了，并且数据存储在influxdb中。接下来配置grafana将数据进行可视化。

因为docker-compose-monitor.yml文件内给grafna配置的端口是80,这里直接访问master机器的IP就可以访问到grafana,在浏览器打开192.168.1.60.
grafana
默认的帐号是admin
默认的密码是admin
首次登陆后会提示修改密码，新密码继续设置为admin也没关系。

登陆成功后开始设置数据源

配置数据源

打开左边菜单栏进入数据源配置页面

添加新的数据源,我这里是添加过了,所以会有一个influxdb的数据源显示。

选择influxdb类型的数据源

填写influxdb对应的信息,Name填写influx,因为待会要用到一个grafana模版,所以这里叫influx名字,URL填http://influx:8086,这个也不是固定的,本次docker-compose-monitor.yml文件内influxdb的容器名叫influx,端口开放出来的为8086(默认),所以这里填influx:8086