Docker实践—CentOS7上部署Kubernetes详解

时间:2021-09-08 07:19:48

Kubernetes架构

Kubernetes的整体架构如下:

Docker实践—CentOS7上部署Kubernetes详解

Master为主控节点,上面运行apiserver,scheduler,controller-manager等组件。Minion相当于工作节点,上面运行kubelet,proxy,cAdvisor以及最重要的docker等组件。下面来实际部署一下这套集群管理工具。

环境

yy1  10.193.6.35

yy2  10.193.6.36

yy1作为master,yy2作为minion。

# cat /etc/centos-release

CentOS Linux release 7.0.1406 (Core) 

安装kubernetes

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# curl https://copr.fedoraproject.org/coprs/eparis/kubernetes-epel-7/repo/epel-7/eparis-kubernetes-epel-7-epel-7.repo -o /etc/yum.repos.d/eparis-kubernetes-epel-7-epel-7.repo
 
# yum install kubernetes -y

配置yy1

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# cat /etc/kubernetes/apiserver
 
###
 
# kubernetes system config
 
#
 
# The following values are used to configure the kubernetes-apiserver
 
#
 
 
 
# The address on the local server to listen to.
 
KUBE_API_ADDRESS="10.193.6.35"
 
 
 
# The port on the local server to listen on.
 
KUBE_API_PORT="8080"
 
 
 
# How the replication controller and scheduler find the apiserver
 
KUBE_MASTER="10.193.6.35:8080"
 
 
 
# Comma seperated list of minions
 
MINION_ADDRESSES="10.193.6.36"
 
 
 
# Port minions listen on
 
MINION_PORT="10250"
 
 
 
# cat /etc/kubernetes/config
 
###
 
# kubernetes system config
 
#
 
# The following values are used to configure various aspects of all
 
# kubernetes services, including
 
#
 
#  kubernetes-apiserver.service
 
#  kubernetes-controller-manager.service
 
#  kubernetes-kubelet.service
 
#  kubernetes-proxy.service
 
 
 
# Comma seperated list of nodes in the etcd cluster
 
KUBE_ETCD_SERVERS="http://10.193.6.35:4001"
 
 
 
# logging to stderr means we get it in the systemd journal
 
KUBE_LOGTOSTDERR="true"
 
 
 
# journal message level, 0 is debug
 
KUBE_LOG_LEVEL=0
 
 
 
# Should this cluster be allowed to run privleged docker containers
 
KUBE_ALLOW_PRIV="true"

启动yy1上相关服务

master上需要运行etcd,kube-apiserver,kube-controller-manager,kube-scheduler这4个进程。

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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

配置yy2

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# cat /etc/kubernetes/kubelet
 
###
 
# kubernetes kublet (minion) config
 
 
 
# The address for the info server to serve on
 
MINION_ADDRESS="10.193.6.36"
 
 
 
# The port for the info server to serve on
 
MINION_PORT="10250"
 
# You may leave this blank to use the actual hostname
 
MINION_HOSTNAME="10.193.6.36"
 
# cat /etc/kubernetes/config
 
###
 
# kubernetes system config
 
#
 
# The following values are used to configure various aspects of all
 
# kubernetes services, including
 
#
 
#  kubernetes-apiserver.service
 
#  kubernetes-controller-manager.service
 
#  kubernetes-kubelet.service
 
#  kubernetes-proxy.service
 
# Comma seperated list of nodes in the etcd cluster
 
KUBE_ETCD_SERVERS="http://10.193.6.35:4001"
 
 
 
# logging to stderr means we get it in the systemd journal
 
KUBE_LOGTOSTDERR="true"
 
# journal message level, 0 is debug
 
KUBE_LOG_LEVEL=0
 
# Should this cluster be allowed to run privleged docker containers
 
KUBE_ALLOW_PRIV="true"

修改yy2 kubelet的配置

CentOS7上没有docker.socket服务,注释掉kubelet中对docker.socket的依赖。

/usr/lib/systemd/system/kubelet.service

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[Unit]
 
Description=Kubernetes Kubelet
 
#After=docker.socket cadvisor.service
 
After=cadvisor.service
 
#Requires=docker.socket cadvisor.service
 
Requires=cadvisor.service

启动yy2上的相关服务

minion上需要运行kube-proxy,kubelet以及docker。

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

创建pod描述文件

创建一个apache的pod描述文件。

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# cat apache.json
 
{
 
 "id": "apache",
 
 "desiredState": {
 
  "manifest": {
 
   "version": "v1beta1",
 
   "id": "apache-1",
 
   "containers": [{
 
    "name": "master",
 
    "image": "fedora/apache",
 
    "ports": [{
 
     "containerPort": 80,
 
     "hostPort": 80
 
    }]
 
   }]
 
  }
 
 },
 
 "labels": {
 
  "name": "apache"
 
 }
 
}

创建pod

通过客户端工具kubecfg提交任务给apiserver,由scheduler选择一个minion部署容。

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[root@yy1 ~]# kubecfg -c apache.json create pods
 
I0925 06:43:26.768122 09313 request.go:292] Waiting for completion of /operations/1
 
ID         Image(s)      Host        Labels       Status
 
----------     ----------     ----------     ----------     ----------
 
apache       fedora/apache    /          name=apache     Waiting
 
 
 
[root@yy1 ~]# kubecfg list pods
 
ID         Image(s)      Host        Labels       Status
 
----------     ----------     ----------     ----------     ----------
 
apache       fedora/apache    10.193.6.36/    name=apache     Waiting

apache服务会自动部署到机器yy2,yy2上的docker会自动下载image,然后启动apache服务。顺利的话,过一会儿,apache服务就会在yy2上起来。

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[root@yy1 ~]# kubecfg list pods
 
ID         Image(s)      Host        Labels       Status
 
----------     ----------     ----------     ----------     ----------
 
apache       fedora/apache    10.193.6.36/    name=apache     Running

Docker实践—CentOS7上部署Kubernetes详解

可以尝试访问一下,

Docker实践—CentOS7上部署Kubernetes详解

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原文链接:http://www.cnblogs.com/hustcat/p/3993712.html