如何在CentOS 7上设置本地OpenShift Origin(OKD)集群
在我们最近的文章中，我们介绍了OpenShift 4的新功能。OpenShift4是每个人都在等待的最佳Kubernetes发行版。 Openshift为我们提供了一个自助服务平台，可以根据需要创建，修改和部署容器化的应用程序。本教程将深入介绍在CentOS 7 VM上安装OpenShift Origin(OKD)3.x。
OpenShift开发团队在简化OpenShift群集设置方面所做的工作值得称赞。只需一个命令即可获得运行的OKD Local集群。
对于Ubuntu，请使用：如何在Ubuntu上设置OpenShift Origin(OKD)
我的设置是在具有以下硬件配置的虚拟机上完成的.8 vCPU 32 GB RAM 50 GB可用磁盘空间CentOS 7 OS
请按照下一部分中介绍的步骤在CentOS 7虚拟机上部署OpenShift Origin Local集群。
更新CentOS 7系统
让我们开始更新我们的CentOS 7机器。
sudo yum -y update
安装和配置Docker
OpenShift需要主机上的docker引擎才能运行容器。使用以下命令在CentOS 7上安装Docker。
sudo yum install -y yum-utils device-mapper-persistent-data lvm2 sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo sudo yum install -y docker-ce docker-ce-cli containerd.io
将标准用户帐户添加到docker组。
sudo usermod -aG docker $USER newgrp docker
安装Docker之后，使用不安全的注册表参数172.30.0.0/16配置Docker守护进程
sudo mkdir /etc/docker /etc/containers
sudo tee /etc/containers/registries.conf<<EOF
[registries.insecure]
registries = ['172.30.0.0/16']
EOF
sudo tee /etc/docker/daemon.json<<EOF
{
"insecure-registries": [
"172.30.0.0/16"
]
}
EOF
编辑配置后，我们需要重新加载systemd并重新启动Docker守护程序。
sudo systemctl daemon-reload sudo systemctl restart docker
使Docker在启动时启动。
$sudo systemctl enable docker Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.
然后在系统上启用IP转发。
echo "net.ipv4.ip_forward = 1" | sudo tee -a /etc/sysctl.conf sudo sysctl -p
配置防火墙。
确保防火墙允许容器访问OpenShift主API(8443/tcp)和DNS(53/udp)端点。
DOCKER_BRIDGE=`docker network inspect -f "{{range .IPAM.Config }}{{ .Subnet }}{{end}}" bridge`
sudo firewall-cmd --permanent --new-zone dockerc
sudo firewall-cmd --permanent --zone dockerc --add-source $DOCKER_BRIDGE
sudo firewall-cmd --permanent --zone dockerc --add-port={80,443,8443}/tcp
sudo firewall-cmd --permanent --zone dockerc --add-port={53,8053}/udp
sudo firewall-cmd --reload
下载Linux oc二进制文件
在此步骤中，我们可以从openshift-origin-client-tools-VERSION-linux-64bit.tar.gz下载Linux oc二进制文件并将其放在路径中。
wget https://github.com/openshift/origin/releases/download/v3.11.0/openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit.tar.gz tar xvf openshift-origin-client-tools*.tar.gz cd openshift-origin-client*/ sudo mv oc kubectl /usr/local/bin/
验证OpenShift客户端实用程序的安装。
$oc version oc v3.11.0+0cbc58b kubernetes v1.11.0+d4cacc0 features: Basic-Auth GSSAPI Kerberos SPNEGO
启动OpenShift Origin(OKD)本地群集
现在，通过运行以下命令来引导本地单服务器OpenShift Origin群集：
$oc cluster up
上面的命令将：在本地接口上启动OKD集群侦听127.0.0.1:8443在/console(127.0.0.1:8443)上启动侦听所有接口的Web控制台启动Kubernetes系统组件设置注册表，路由器，初始模板，以及默认项目。OpenShift集群将在Docker主机上作为多合一容器运行。
设置Openshift Origin时可以应用许多选项，请使用以下方法查看它们：
$oc cluster up --help
成功安装后，我们应该获得与以下类似的输出。
Login to server …
Creating initial project "myproject" …
Server Information …
OpenShift server started.
The server is accessible via web console at:
https://127.0.0.1:8443
You are logged in as:
User: developer
Password: <any value>
To login as administrator:
oc login -u system:admin
下面的示例使用自定义选项。
$oc cluster up --routing-suffix=<ServerPublicIP>.xip.io \ --public-hostname=<ServerPulicDNSName>
例。
$oc cluster up --public-hostname=okd.example.com --routing-suffix='services.example.com'
OpenShift Origin集群配置文件将位于openshift.local.clusterup /目录中。
如果集群安装成功，则以下命令应获得肯定的输出。
$oc cluster status Web console URL: https://okd.example.com:8443/console/ Config is at host directory Volumes are at host directory Persistent volumes are at host directory /home/dev/openshift.local.clusterup/openshift.local.pv Data will be discarded when cluster is destroyed
使用OpenShift Origin Cluster
要以管理员身份登录，请使用：
$oc login -u system:admin
Logged into "https://127.0.0.1:8443" as "system:admin" using existing credentials.
You have access to the following projects and can switch between them with 'oc project <projectname>':
* default
kube-dns
kube-proxy
kube-public
kube-system
myproject
openshift
openshift-apiserver
openshift-controller-manager
openshift-core-operators
openshift-infra
openshift-node
openshift-service-cert-signer
openshift-web-console
testproject
Using project "default".
作为系统管理员用户，我们几乎看不到诸如节点状态之类的信息。
$oc get nodes NAME STATUS ROLES AGE VERSION localhost Ready <none> 1h v1.11.0+d4cacc0 $oc get nodes -o wide
要获取有关特定节点的更多详细信息，包括当前状况的原因：
$oc describe node <node>
要显示我们创建的资源的摘要：
$oc status
In project default on server https://127.0.0.1:8443
svc/docker-registry - 172.30.1.1:5000
dc/docker-registry deploys docker.io/openshift/origin-docker-registry:v3.11
deployment #1 deployed 2 hours ago - 1 pod
svc/kubernetes - 172.30.0.1:443 -> 8443
svc/router - 172.30.235.156 ports 80, 443, 1936
dc/router deploys docker.io/openshift/origin-haproxy-router:v3.11
deployment #1 deployed 2 hours ago - 1 pod
View details with 'oc describe <resource>/<name>' or list everything with 'oc get all'.
要返回普通的" developer"用户，请以该用户身份登录：
$oc login Authentication required for https://127.0.0.1:8443 (openshift) Username: developer Password: developer Login successful.
确认登录是否成功。
$oc whoami developer
让我们使用oc new-project命令创建一个测试项目。
$oc new-project dev --display-name="Project1 - Dev" \ --description="My Dev Project" Now using project "dev" on server "https://127.0.0.1:8443".
使用OKD管理控制台
OKD包括一个Web控制台，可用于创建和管理操作。该Web控制台可通过https在端口" 8443"上的服务器IP /主机名上访问。
https://<IP|Hostname>:8443/console
我们应该看到带有用户名和密码形式的OpenShift Origin窗口，类似于以下窗口：
登录：
Username: developer Password: developer
我们应该看到类似于以下内容的仪表板。
如果在尝试访问OpenShift Web控制台时重定向到https://127.0.0.1:8443/，请执行以下操作：
1.停止OpenShift集群
$oc cluster down
2.编辑OCP配置文件。
$vi ./openshift.local.clusterup/openshift-controller-manager/openshift-master.kubeconfig
找到线路服务器：https：//127.0.0.1：8443，然后替换为：
server: https://serverip:8443
3.然后启动集群：
$oc cluster up
部署测试应用程序
现在，我们可以在集群中部署测试应用程序。
1.登录到Openshift集群：
$oc login
Authentication required for https://https://127.0.0.1:8443 (openshift)
Username: developer
Password: developer
Login successful.
You don't have any projects. You can try to create a new project, by running
oc new-project
2.创建一个测试项目。
$oc new-project test-project
3.从Docker Hub注册表中标记应用程序镜像。
$oc tag --source=docker openshift/deployment-example:v2 deployment-example:latest Tag deployment-example:latest set to openshift/deployment-example:v2.
4.将应用程序部署到OpenShift。
$oc new-app deployment-example
--> Found image da61bb2 (3 years old) in image stream "test-project/deployment-example" under tag "latest" for "deployment-example"
* This image will be deployed in deployment config "deployment-example"
* Port 8080/tcp will be load balanced by service "deployment-example"
* Other containers can access this service through the hostname "deployment-example"
* WARNING: Image "test-project/deployment-example:latest" runs as the 'root' user which Jan not be permitted by your cluster administrator
--> Creating resources ...
deploymentconfig.apps.openshift.io "deployment-example" created
service "deployment-example" created
--> Success
Application is not exposed. You can expose services to the outside world by executing one or more of the commands below:
'oc expose svc/deployment-example'
Run 'oc status' to view your app.
5.显示应用程序部署状态。
$oc status
In project test-project on server https://127.0.0.1:8443
svc/deployment-example - 172.30.15.201:8080
dc/deployment-example deploys istag/deployment-example:latest
deployment #1 deployed about a minute ago - 1 pod
2 infos identified, use 'oc status --suggest' to see details.
6.获取服务详细信息。
$oc get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE deployment-example ClusterIP 172.30.15.201 8080/TCP 18m $oc describe svc deployment-example Name: deployment-example Namespace: test-project Labels: app=deployment-example Annotations: openshift.io/generated-by=OpenShiftNewApp Selector: app=deployment-example,deploymentconfig=deployment-example Type: ClusterIP IP: 172.30.15.201 Port: 8080-tcp 8080/TCP TargetPort: 8080/TCP Endpoints: 172.17.0.12:8080 Session Affinity: None Events: <none>
7.测试应用程序本地访问。
curl http://172.30.15.201:8080
8.显示窗格状态
$oc get pods NAME READY STATUS RESTARTS AGE deployment-example-1-vmf7t 1/1 Running 0 21m
9.允许外部访问该应用程序。
$oc expose service/deployment-example route.route.openshift.io/deployment-example exposed $oc get routes NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD deployment-example deployment-example-testproject.services.theitroad.local deployment-example 8080-tcp None
10.测试对应用程序的外部访问。
打开浏览器中显示的URL。
请注意，我具有* .services.theitroad.local的通配符DNS记录，该记录指向OpenShift源服务器IP地址。
11.删除测试申请
$oc delete all -l app=deployment-example pod "deployment-example-1-8n8sd" deleted replicationcontroller "deployment-example-1" deleted service "deployment-example" deleted deploymentconfig.apps.openshift.io "deployment-example" deleted route.route.openshift.io "deployment-example" deleted $oc get pods No resources found.
