為什么是deploymentconfig而不是Kubernetes的deployment
在new-app的時候openshift直接創建了一個deploymentconfig並部署成rc,開始並不理解為什么要這么做，后來看到下面這個命令才大概明白，原因主要有兩點：
- deploymentconfig在創建的時候通過new-app自動生成，避免直接從無到有去寫一個deployment的yaml文件，減少了出錯。
- deployment並不具備回滾的功能，如果部署到一個版本就無法回滾到上一個版本或者更前一個版本了，而dc有個revision,同時保留了之前部署版本的配置。如下：
如果回滾可以通過下面命令
oc rollback openshift-tomcat --to-version=2
- 創建new-app的時候除了創建dc,還會創建一個服務，名字和app名字一樣
如果需要在容器運行前就帶入環境變量
oc new-app openshift-tomcat --name=openshift-tomcat --env DEPLOY_MODE=stg
帶入多個
C:\minishift-1.26.1-windows-amd64>oc new-app openshift-tomcat --name=openshift-tomcat --env DEPLOY_MODE=stg SITE=sz warning: Cannot find git. Ensure that it is installed and in your path. Git is required to work with git repositories. --> Found image a4dc2a4 (6 hours old) in image stream "myproject/openshift-tomcat" under tag "latest" for "openshift-tomcat" temp.builder.openshift.io/myproject/openshift-tomcat-3:d91ff45d --------------------------------------------------------------- Platform for building and running JEE applications on Tomcat Tags: builder, tomcat * This image will be deployed in deployment config "openshift-tomcat" * Port 8080/tcp will be load balanced by service "openshift-tomcat" * Other containers can access this service through the hostname "openshift-tomcat" --> Creating resources ... deploymentconfig.apps.openshift.io "openshift-tomcat" created service "openshift-tomcat" 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/openshift-tomcat' Run 'oc status' to view your app.
容器運行中設置環境變量
C:\minishift-1.26.1-windows-amd64>oc set env dc/openshift-tomcat DEPLOY_MODE="prd" deploymentconfig.apps.openshift.io/openshift-tomcat updated
列出環境變量
C:\minishift-1.26.1-windows-amd64>oc set env dc/openshift-tomcat --list # deploymentconfigs/openshift-tomcat, container openshift-tomcat DEPLOY_MODE=stg