By Valleylord

更新日期:

文章目录
  1. 1. 物理环境和网络
  2. 2. yum 源配置
  3. 3. 安装 Kubernetes
  4. 4. 节点配置
  5. 5. 主节点配置和启动
  6. 6. 工作节点配置和启动
  7. 7. 检查 Kubernetes 运行
  8. 8. 常用脚本
  9. 9. 启动一个 mysql

本文主要参考12。

物理环境和网络

理论上，Kubernetes将服务放在两台主机上。第一台主机，centos-master，是 Kubernetes 主节点，主要运行kube-apiserver, kube-controller-manager, 和 kube-scheduler，以及 etcd。另一台主机，centos-minion，是工作节点，主要运行 kubelet, proxy, cadvisor 和 docker。

本文简单处理，物理机只有1台，分别配置 host 如下。

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192.168.2.202   centos-master
192.168.2.202   centos-minion

centos-master 操作系统是 Centos 7。

yum 源配置

增加 Kubernetes 的 yum 源，sudo vi /etc/yum.repos.d/virt7-docker-common-release.repo，

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[virt7-docker-common-release]
name=virt7-docker-common-release
baseurl=http://cbs.centos.org/repos/virt7-docker-common-release/x86_64/os/
gpgcheck=0

安装 Kubernetes

注意：Kubernetes 目前尚不能支持 Docker 的最新版，如果本机已经安装 Docker，建议先删除 Docker。

由于已经配置 yum 源，安装就比较简单，

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yum install --enablerepo=virt7-docker-common-release kubernetes etcd

节点配置

在所有主机上，做如下配置，vi /etc/kubernetes/config，

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# logging to stderr means we get it in the systemd journal
KUBE_LOGTOSTDERR="--logtostderr=true"
# journal message level, 0 is debug
KUBE_LOG_LEVEL="--v=0"
# Should this cluster be allowed to run privileged docker containers
KUBE_ALLOW_PRIV="--allow-privileged=false"
# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://centos-master:8080"
# Comma separated list of nodes in the etcd cluster
KUBE_ETCD_SERVERS="--etcd-servers=http://centos-master:2379"

注意，上述的 KUBE_ETCD_SERVERS 参数要根据 etcd 的实际情况来配置，etcd 的配置请在 /etc/etcd/etcd.conf。

在主节点和工作节点上禁用防火墙，因为 docker 并不擅长防火墙规则管理，

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systemctl disable iptables-services firewalld
systemctl stop iptables-services firewalld

主节点配置和启动

在主节点上配置如下，vi /etc/kubernetes/apiserver

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# The address on the local server to listen to.
KUBE_API_ADDRESS="--address=0.0.0.0"
# The port on the local server to listen on.
KUBE_API_PORT="--port=8080"
# How the replication controller and scheduler find the kube-apiserver
KUBE_MASTER="--master=http://centos-master:8080"
# Port kubelets listen on
KUBELET_PORT="--kubelet-port=10250"
# Address range to use for services
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
# Add your own!
KUBE_API_ARGS=""

然后用以下命令启动，

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for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do 
    systemctl restart $SERVICES
    systemctl enable $SERVICES
    systemctl status $SERVICES 
done

将以上脚本保存在脚本start_kubernetes.sh中。以下是运行输出，

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[root@Centos-L410 kubernetes]# ./start_kubernetes.sh 
● etcd.service - Etcd Server
   Loaded: loaded (/usr/lib/systemd/system/etcd.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:04:49 CST; 188ms ago
 Main PID: 24669 (etcd)
   CGroup: /system.slice/etcd.service
           └─24669 /usr/bin/etcd --name=default --data-dir=/var/lib/etcd/default.etcd --listen-client-urls=http://cen...
2月 28 18:04:49 Centos-L410 etcd[24669]: election = 1000ms
2月 28 18:04:49 Centos-L410 etcd[24669]: snapshot count = 10000
2月 28 18:04:49 Centos-L410 etcd[24669]: advertise client URLs = http://centos-master:2379
2月 28 18:04:49 Centos-L410 etcd[24669]: restarting member ce2a822cea30bfca in cluster 7e27652122e8b2ae at comm... 8613
2月 28 18:04:49 Centos-L410 etcd[24669]: ce2a822cea30bfca became follower at term 7
2月 28 18:04:49 Centos-L410 etcd[24669]: newRaft ce2a822cea30bfca [peers: [], term: 7, commit: 8613, applied: 0...m: 7]
2月 28 18:04:49 Centos-L410 etcd[24669]: starting server... [version: 2.2.2, cluster version: to_be_decided]
2月 28 18:04:49 Centos-L410 systemd[1]: Started Etcd Server.
2月 28 18:04:49 Centos-L410 etcd[24669]: added local member ce2a822cea30bfca [http://localhost:2380 http://loca...8b2ae
2月 28 18:04:49 Centos-L410 etcd[24669]: set the initial cluster version to 2.2
Hint: Some lines were ellipsized, use -l to show in full.
● kube-apiserver.service - Kubernetes API Server
   Loaded: loaded (/usr/lib/systemd/system/kube-apiserver.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:04:52 CST; 152ms ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 24726 (kube-apiserver)
   CGroup: /system.slice/kube-apiserver.service
           └─24726 /usr/bin/kube-apiserver --logtostderr=true --v=0 --etcd-servers=http://centos-master:2379 --addres...
2月 28 18:04:50 Centos-L410 systemd[1]: Starting Kubernetes API Server...
2月 28 18:04:52 Centos-L410 systemd[1]: Started Kubernetes API Server.
● kube-controller-manager.service - Kubernetes Controller Manager
   Loaded: loaded (/usr/lib/systemd/system/kube-controller-manager.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:04:52 CST; 207ms ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 24777 (kube-controller)
   CGroup: /system.slice/kube-controller-manager.service
           └─24777 /usr/bin/kube-controller-manager --logtostderr=true --v=0 --master=http://centos-master:8080
2月 28 18:04:52 Centos-L410 systemd[1]: Started Kubernetes Controller Manager.
2月 28 18:04:52 Centos-L410 systemd[1]: Starting Kubernetes Controller Manager...
2月 28 18:04:52 Centos-L410 kube-controller-manager[24777]: I0228 18:04:52.714705   24777 plugins.go:71] No cloud...ed.
2月 28 18:04:52 Centos-L410 kube-controller-manager[24777]: I0228 18:04:52.722761   24777 nodecontroller.go:133] ...er.
2月 28 18:04:52 Centos-L410 kube-controller-manager[24777]: E0228 18:04:52.722944   24777 controllermanager.go:27...er.
Hint: Some lines were ellipsized, use -l to show in full.
● kube-scheduler.service - Kubernetes Scheduler Plugin
   Loaded: loaded (/usr/lib/systemd/system/kube-scheduler.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:04:52 CST; 187ms ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 24829 (kube-scheduler)
   CGroup: /system.slice/kube-scheduler.service
           └─24829 /usr/bin/kube-scheduler --logtostderr=true --v=0 --master=http://centos-master:8080
2月 28 18:04:52 Centos-L410 systemd[1]: Started Kubernetes Scheduler Plugin.
2月 28 18:04:52 Centos-L410 systemd[1]: Starting Kubernetes Scheduler Plugin...

工作节点配置和启动

在工作节点上配置如下，vi /etc/kubernetes/kubelet，

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# The address for the info server to serve on
KUBELET_ADDRESS="--address=0.0.0.0"
# The port for the info server to serve on
KUBELET_PORT="--port=10250"
# You may leave this blank to use the actual hostname
KUBELET_HOSTNAME="--hostname-override=centos-minion"
# Location of the api-server
KUBELET_API_SERVER="--api-servers=http://centos-master:8080"
# Add your own!
KUBELET_ARGS=""

然后用以下命令启动，

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for SERVICES in kube-proxy kubelet docker; do 
    systemctl restart $SERVICES
    systemctl enable $SERVICES
    systemctl status $SERVICES 
done

将以上脚本保存在脚本start_kubernetes_work.sh中。以下是运行输出，

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[root@Centos-L410 kubernetes]# ./start_kubernetes_work.sh 
● kube-proxy.service - Kubernetes Kube-Proxy Server
   Loaded: loaded (/usr/lib/systemd/system/kube-proxy.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:05:15 CST; 307ms ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 24880 (kube-proxy)
   CGroup: /system.slice/kube-proxy.service
           ├─24880 /usr/bin/kube-proxy --logtostderr=true --v=0 --master=http://centos-master:8080
           └─24939 iptables -w -C KUBE-PORTALS-HOST -t nat -m comment --comment default/kubernetes:https -p tcp -m tc...
2月 28 18:05:15 Centos-L410 systemd[1]: Started Kubernetes Kube-Proxy Server.
2月 28 18:05:15 Centos-L410 systemd[1]: Starting Kubernetes Kube-Proxy Server...
2月 28 18:05:15 Centos-L410 kube-proxy[24880]: E0228 18:05:15.932316   24880 server.go:324] Not trying iptables...found
2月 28 18:05:15 Centos-L410 kube-proxy[24880]: E0228 18:05:15.966946   24880 proxier.go:193] Error removing pur...ctory
2月 28 18:05:15 Centos-L410 kube-proxy[24880]: Try `iptables -h' or 'iptables --help' for more information.
2月 28 18:05:15 Centos-L410 kube-proxy[24880]: E0228 18:05:15.970419   24880 proxier.go:197] Error removing pur...ctory
2月 28 18:05:15 Centos-L410 kube-proxy[24880]: Try `iptables -h' or 'iptables --help' for more information.
Hint: Some lines were ellipsized, use -l to show in full.
● kubelet.service - Kubernetes Kubelet Server
   Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:05:17 CST; 282ms ago
     Docs: https://github.com/GoogleCloudPlatform/kubernetes
 Main PID: 25036 (kubelet)
   CGroup: /system.slice/kubelet.service
           └─25036 /usr/bin/kubelet --logtostderr=true --v=0 --api-servers=http://centos-master:8080 --address=0.0.0....
2月 28 18:05:17 Centos-L410 systemd[1]: Started Kubernetes Kubelet Server.
2月 28 18:05:17 Centos-L410 systemd[1]: Starting Kubernetes Kubelet Server...
● docker.service - Docker Application Container Engine
   Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled; vendor preset: disabled)
   Active: active (running) since 日 2016-02-28 18:05:18 CST; 245ms ago
     Docs: http://docs.docker.com
 Main PID: 25120 (docker)
   CGroup: /system.slice/docker.service
           └─25120 /usr/bin/docker daemon
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.069063505+08:00" level=info msg="Option De...idge"
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.069114767+08:00" level=info msg="Option De...idge"
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.081358591+08:00" level=warning msg="Runnin...us 1"
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.089480121+08:00" level=info msg="Firewalld...alse"
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.386325219+08:00" level=info msg="Loading c...art."
2月 28 18:05:18 Centos-L410 docker[25120]: ..........
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.391606225+08:00" level=info msg="Loading c...one."
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.391633742+08:00" level=info msg="Daemon ha...tion"
2月 28 18:05:18 Centos-L410 docker[25120]: time="2016-02-28T18:05:18.391658744+08:00" level=info msg="Docker da...entos
2月 28 18:05:18 Centos-L410 systemd[1]: Started Docker Application Container Engine.
Hint: Some lines were ellipsized, use -l to show in full.

检查 Kubernetes 运行

运行以下命令可以查到工作节点，

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[root@Centos-L410 kubernetes]# kubectl get nodes
NAME            LABELS                                 STATUS    AGE
centos-minion   kubernetes.io/hostname=centos-minion   Ready     50s
[root@Centos-L410 kubernetes]# kubectl cluster-info
Kubernetes master is running at http://localhost:8080

常用脚本

常用的 Kubernetes 的脚本，总共6个，分别是对主节点和工作节点的启动、停止和获取状态，如下，

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#!/bin/bash
#start_kubernetes.sh
for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do 
    systemctl restart $SERVICES
    systemctl enable $SERVICES
    systemctl status $SERVICES 
done

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#!/bin/bash
#start_kubernetes_work.sh
for SERVICES in kube-proxy kubelet docker; do 
    systemctl restart $SERVICES
    systemctl enable $SERVICES
    systemctl status $SERVICES 
done

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#!/bin/bash
#status_kubernetes.sh
for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do 
    systemctl status $SERVICES 
done

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#!/bin/bash
#status_kubernetes_work.sh
for SERVICES in kube-proxy kubelet docker; do 
    systemctl status $SERVICES 
done

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#!/bin/bash
#stop_kubernetes.sh
for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do 
    systemctl stop $SERVICES
done

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#!/bin/bash
#stop_kubernetes_work.sh
for SERVICES in kube-proxy kubelet docker; do 
    systemctl stop $SERVICES
done

启动一个 mysql

新建一个 mysql-pod.yaml 文件，用于描述 pod，

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apiVersion: v1
kind: Pod
metadata:
  name: mysql
  labels:
    name: mysql
spec:
  containers:
    - resources:
        limits :
          cpu: 0.5
      image: docker.io/mysql
      name: mysql
      env:
        - name: MYSQL_ROOT_PASSWORD
          # change this
          value: "111111"
      ports:
        - containerPort: 3306
          hostPort: 3326
          name: mysql
      volumeMounts:
          # name must match the volume name below
        - name: mysql-persistent-storage
          # mount path within the container
          mountPath: /var/lib/mysql
  volumes:
    - name: mysql-persistent-storage
      hostPath:
        path: /home/arnes/kubernetes/mysql-kube-data

然后启动这个 pod，检查状态，

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[root@Centos-L410 kubernetes]# kubectl create -f mysql-pod.yaml 
pod "mysql" created
[root@Centos-L410 kubernetes]# kubectl get pods
NAME      READY     STATUS    RESTARTS   AGE
mysql     0/1       Pending   0          31s
[root@Centos-L410 kubernetes]# kubectl get pods mysql
NAME      READY     STATUS    RESTARTS   AGE
mysql     1/1       Running   0          8s
[root@Centos-L410 kubernetes]# kubectl describe pod mysql 
Name:				mysql
Namespace:			default
Image(s):			docker.io/mysql
Node:				centos-minion/192.168.2.202
Start Time:			Sun, 28 Feb 2016 22:21:48 +0800
Labels:				name=mysql
Status:				Running
Reason:				
Message:			
IP:				172.17.1.26
Replication Controllers:	<none>
Containers:
  mysql:
    Container ID:	docker://4ea08f19a85e71084bef939524f9adffd733944744fdb31dcfd25ba2ccb087fb
    Image:		docker.io/mysql
    Image ID:		docker://082e0ea24cc00eced7b39d88f46e508ab83298f79e008b1e5d7fb0c928ff692b
    QoS Tier:
      cpu:	Guaranteed
      memory:	BestEffort
    Limits:
      cpu:	500m
    Requests:
      cpu:		500m
    State:		Running
      Started:		Sun, 28 Feb 2016 22:21:55 +0800
    Ready:		True
    Restart Count:	0
    Environment Variables:
      MYSQL_ROOT_PASSWORD:	111111
Conditions:
  Type		Status
  Ready 	True 
Volumes:
  mysql-persistent-storage:
    Type:	HostPath (bare host directory volume)
    Path:	/home/arnes/kubernetes/mysql-kube-data
Events:
  FirstSeen	LastSeen	Count	From			SubobjectPath				Reason		Message
  ─────────	────────	─────	────			─────────────				──────		───────
  4m		4m		1	{scheduler }							Scheduled	Successfully assigned mysql to centos-minion
  4m		4m		1	{kubelet centos-minion}	implicitly required container POD	Pulled		Container image "registry.access.redhat.com/rhel7/pod-infrastructure:latest" already present on machine
  4m		4m		1	{kubelet centos-minion}	implicitly required container POD	Created		Created with docker id 84660e3722fa
  4m		4m		1	{kubelet centos-minion}	implicitly required container POD	Started		Started with docker id 84660e3722fa
  4m		4m		1	{kubelet centos-minion}	spec.containers{mysql}			Pulled		Container image "docker.io/mysql" already present on machine
  4m		4m		1	{kubelet centos-minion}	spec.containers{mysql}			Created		Created with docker id 4ea08f19a85e
  4m		4m		1	{kubelet centos-minion}	spec.containers{mysql}			Started		Started with docker id 4ea08f19a85e

  1. https://github.com/kubernetes/kubernetes/blob/release-1.1/docs/getting-started-guides/centos/centos_manual_config.md↩

  2. http://www.mamicode.com/info-detail-1129211.html↩

文章目录
  1. 1. 物理环境和网络
  2. 2. yum 源配置
  3. 3. 安装 Kubernetes
  4. 4. 节点配置
  5. 5. 主节点配置和启动
  6. 6. 工作节点配置和启动
  7. 7. 检查 Kubernetes 运行
  8. 8. 常用脚本
  9. 9. 启动一个 mysql

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