Docker实践—CentOS7上部署Kubernetes详解
作者：YY哥
kubernetes作为docker的管理工具是由Google开源提供，但是kubernetes的安装一直折磨着运维人员，在这一系列的文章中我将会由kubernetes的安装讲起为大家介绍kubernetes的安装使用等过程，也作为自己的学习笔记。
Kubernetes架构
Kubernetes的整体架构如下：
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
# 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
# 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。
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
# 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
[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。
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。
# 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。
[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。
[root@yy1 ~]# kubecfg list pods ID Image(s) Host Labels Status ---------- ---------- ---------- ---------- ---------- apache fedora/apache 10.193.6.36/ name=apache Running
可以尝试访问一下，
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。