红帽全球峰会4.5.3. 扩展应用程序
在 Kubernetes 中，Deployment 对象定义了应用的部署方式。在大多数情况下，用户会一起使用 Pod, Service, ReplicaSets, 和 Deployment 资源。在大多数情况下，OpenShift Container Platform 会为您创建资源。
当您部署 national-parks-app 镜像时，会创建一个部署资源。在本例中，只部署了一个 Pod。
以下流程将 national-parks-image 扩展为使用两个实例。
先决条件
- 有访问 OpenShift Container Platform 集群的权限。
-
已安装 OpenShift CLI（
oc）。 - 您已部署了一个镜像。
流程
要将应用程序从一个 pod 实例扩展到两个 pod 实例，请输入以下命令：
$ oc scale --current-replicas=1 --replicas=2 deployment/parksmap输出示例
deployment.apps/parksmap scaled
验证
要确保应用程序正确扩展，请输入以下命令：
$ oc get pods输出示例
NAME READY STATUS RESTARTS AGE parksmap-5f9579955-6sng8 1/1 Running 0 7m39s parksmap-5f9579955-8tgft 1/1 Running 0 24s要将应用程序缩减至一个 pod 实例，请输入以下命令：
$ oc scale --current-replicas=2 --replicas=1 deployment/parksmap
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