记录《kubernetes权威指南》中单机应用栈例子（1）

前期准备工作

使用centos7虚拟机

• 关闭centos防火墙

  systemctl stop firewalldsystemctl disable firewalld

• 安装etcd及kubernetes软件

  yum update -yyum install etcd kubernetes -y

• 安装好的各软件版本如下

kubectl: v1.5.2docker: 1.13.1etcd: 3.2.15

• 修复配置文件
  • docker配置文件/etc/sysconfig/docker

修改为OPTIONS=‘--selinux-enabled=false‘

• • kubernetes apiserver配置文件 /etc/kubernetes/apiserver

KUBE_ADMISSION_CONTROL参数中删除ServiceAccount

• 使用daocloud加速器

注册daocloud用户后，运行daocloud加速器脚本

curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://41379ba5.m.daocloud.io# 由于网络原因，最好使用加速器。# 如果使用daocloud后，出现镜像下载问题，可以考虑替换为阿里云加速器# 实际上就是编辑了/etc/docker/daemon.json文件# 如果docker镜像下载出现问题，优先考虑网络问题。

• 启动服务

systemctl start etcdsystemctl start docker systemctl start kube-apiserversystemctl start kube-controller-managersystemctl start kube-schedulersystemctl start kubeletsystemctl start kube-proxy

• 下载镜像

# mysql镜像docker pull daocloud.io/library/mysql:latest# tomcat镜像docker pull kubeguide/tomcat-app:v2[root@host1 docker]# docker imagesREPOSITORY ??????????????????????TAG ????????????????IMAGE ID ???????????CREATED ????????????SIZEdaocloud.io/library/mysql ???????latest ?????????????80bbf861367a ???????3 days ago ?????????445 MBdocker.io/kubeguide/tomcat-app ??v2 ?????????????????00beaa1d956d ???????21 months ago ??????358 MB

启用mysql容器服务

定义rc模板，命名为mysql-rc.yaml

apiVersion: v1kind: ReplicationControllermetadata: ?name: mysqlspec: ?replicas: 1 ?#定义RC标签选择 ?selector: ???app: mysql ?#定义Pod模板 ?template: ???metadata: ?????labels: ????????app: mysql ???spec: ?????#Pod内容器定义 ?????containers: ???????- name: mysql ?????????# image需要指定docker images输出中的那个mysql镜像 ?????????image: ?daocloud.io/library/mysql:latest ?????????ports: ??????????- containerPort: 3306 ?????????env: ?????????- name: MYSQL_ROOT_PASSWORD ???????????value: "123456"

注意image选择，是与书中不一致的，因为我们下载的mysql镜像是daocloud仓库中的镜像

创建好文件后，发布到kubernetes集群中

[root@host1 kube-test]# kubectl create -f mysql-rc.yamlreplicationcontroller "mysql" created[root@host1 kube-test]# kubectl get rcNAME ?????DESIRED ??CURRENT ??READY ????AGEmysql ????1 ????????1 ????????0 ????????10s[root@host1 kube-test]# kubectl get podsNAME ?????????READY ????STATUS ?????????????RESTARTS ??AGEmysql-nrcvt ??0/1 ??????ContainerCreating ??0 ?????????27s

这个ContainerCreating状态是异常状态，会一直持续，不会进入到running状态

查看pods状态时，

kubectl describe pods mysql-nrcvt............ ?1m ???5s ?5 ??{kubelet 127.0.0.1} ????Warning FailedSync ?Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""

发现是无法下载这个镜像，于是我手动pull这个镜像，发现如下报错：

[root@host1 kube-test]# docker pull registry.access.redhat.com/rhel7/pod-infrastructure:latestTrying to pull repository registry.access.redhat.com/rhel7/pod-infrastructure ... open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory

搜索这个报错，发现可以通过yum install rhsm -y解决
运行该命令后，删除掉之前部署的rc，

[root@host1 kube-test]# kubectl delete rc mysqlreplicationcontroller "mysql" deleted[root@host1 kube-test]# kubectl get podsNo resources found.

重新部署

[root@host1 kube-test]# kubectl create -f mysql-rc.yamlreplicationcontroller "mysql" created[root@host1 kube-test]# kubectl get rcNAME ?????DESIRED ??CURRENT ??READY ????AGEmysql ????1 ????????1 ????????1 ????????7s[root@host1 kube-test]# kubectl get pods NAME ?????????READY ????STATUS ???RESTARTS ??AGEmysql-nbwvp ??1/1 ??????Running ??0 ?????????13s

mysql正常运行了。
查看正在运行的docker，发现有两个

[root@host1 kube-test]# docker ps CONTAINER ID ???????IMAGE ???????????????????????????????????????????????????????COMMAND ?????????????????CREATED ?????????????STATUS ?????????????PORTS ??????????????NAMESf58905ddee64 ???????daocloud.io/library/mysql:latest ????????????????????????????"docker-entrypoint..." ??About a minute ago ??Up About a minute ??????????????????????k8s_mysql.9ef925be_mysql-nbwvp_default_30da097b-4ee8-11e8-a311-000c29f71e04_7ac92ba799382a3dcbf0 ???????registry.access.redhat.com/rhel7/pod-infrastructure:latest ??"/usr/bin/pod" ??????????About a minute ago ??Up About a minute ??????????????????????k8s_POD.1d520ba5_mysql-nbwvp_default_30da097b-4ee8-11e8-a311-000c29f71e04_aad8e14a

记录《kubernetes权威指南》中单机应用栈例子（1）

原文地址：http://blog.51cto.com/duf0913/2112491