本文共 4425 字,大约阅读时间需要 14 分钟。
·
ConfigMap 功能在 Kubernetes1.2 版本中引入,许多应用程序会从配置文件、命令行参数或环境变量中读取配 置信息。ConfigMap API 给我们提供了向容器中注入配置信息的机制,ConfigMap 可以被用来保存单个属性,也 可以用来保存整个配置文件或者 JSON 二进制大对象
$ ls docs/user-guide/configmap/kubectl/game.propertiesui.properties$ cat docs/user-guide/configmap/kubectl/game.propertiesenemies=alienslives=3enemies.cheat=trueenemies.cheat.level=noGoodRottensecret.code.passphrase=UUDDLRLRBABASsecret.code.allowed=truesecret.code.lives=30$ cat docs/user-guide/configmap/kubectl/ui.propertiescolor.good=purplecolor.bad=yellowallow.textmode=truehow.nice.to.look=fairlyNice$ kubectl create configmap game-config --from-file=docs/user-guide/configmap/kubectl
—from-file 指定在目录下的所有文件都会被用在 ConfigMap 里面创建一个键值对,键的名字就是文件名,值就 是文件的内容
只要指定为一个文件就可以从单个文件中创建 ConfigMap
$ kubectl create configmap game-config-2 --from-file=docs/userguide/configmap/kubectl/game.properties$ kubectl get configmaps game-config-2 -o yaml
—from-file 这个参数可以使用多次,你可以使用两次分别指定上个实例中的那两个配置文件,效果就跟指定整个 目录是一样的
使用文字值创建,利用 —from-literal 参数传递配置信息,该参数可以使用多次,格式如下
$ kubectl create configmap special-config --from-literal=special.how=very --fromliteral=special.type=charm$ kubectl get configmaps special-config -o yaml
apiVersion: v1kind: ConfigMapmetadata: name: special-config namespace: defaultdata: special.how: very special.type: charm
apiVersion: v1kind: ConfigMapmetadata: name: env-config namespace: defaultdata: log_level: INFO
apiVersion: v1kind: Podmetadata: name: dapi-test-podspec: containers: - name: test-container image: hub.atguigu.com/library/myapp:v1 command: [ "/bin/sh", "-c", "env" ] env: - name: SPECIAL_LEVEL_KEY valueFrom: configMapKeyRef: name: special-config key: special.how - name: SPECIAL_TYPE_KEY valueFrom: configMapKeyRef: name: special-config key: special.type envFrom: - configMapRef: name: env-config restartPolicy: Never
apiVersion: v1kind: ConfigMapmetadata: name: special-config namespace: defaultdata: special.how: very special.type: charm
apiVersion: v1kind: Podmetadata: name: dapi-test-podspec: containers: - name: test-container image: hub.atguigu.com/library/myapp:v1 command: [ "/bin/sh", "-c", "echo $(SPECIAL_LEVEL_KEY) $(SPECIAL_TYPE_KEY)" ] env: - name: SPECIAL_LEVEL_KEY valueFrom: configMapKeyRef: name: special-config key: special.how - name: SPECIAL_TYPE_KEY valueFrom: configMapKeyRef: name: special-config key: special.type restartPolicy: Never
apiVersion: v1kind: ConfigMapmetadata: name: special-config namespace: defaultdata: special.how: very special.type: charm
在数据卷里面使用这个 ConfigMap,有不同的选项。最基本的就是将文件填入数据卷,在这个文件中,键就是文 件名,键值就是文件内容
apiVersion: v1kind: Podmetadata: name: dapi-test-podspec: containers: - name: test-container image: hub.atguigu.com/library/myapp:v1 command: [ "/bin/sh", "-c", "cat /etc/config/special.how" ] volumeMounts: - name: config-volume mountPath: /etc/config volumes: - name: config-volume configMap: name: special-config restartPolicy: Never
apiVersion: v1kind: ConfigMapmetadata: name: log-config namespace: defaultdata: log_level: INFO---apiVersion: extensions/v1beta1kind: Deploymentmetadata: name: my-nginxspec: replicas: 1 template: metadata: labels: run: my-nginx spec: containers: - name: my-nginx image: hub.atguigu.com/library/myapp:v1 ports: - containerPort: 80 volumeMounts: - name: config-volume mountPath: /etc/config volumes: - name: config-volume configMap: name: log-config
$ kubectl exec `kubectl get pods -l run=my-nginx -o=name|cut -d "/" -f2` cat/etc/config/log_levelINFO
修改 ConfigMap
$ kubectl edit configmap log-config
修改 log_level 的值为 DEBUG 等待大概 10 秒钟时间,再次查看环境变量的值
$ kubectl exec `kubectl get pods -l run=my-nginx -o=name|cut -d "/" -f2` cat /tmp/log_levelDEBUG
ConfigMap 更新后滚动更新 Pod 更新 ConfigMap 目前并不会触发相关 Pod 的滚动更新,可以通过修改 pod annotations 的方式强制触发滚动更新
$ kubectl patch deployment my-nginx --patch '{"spec": {"template": {"metadata": {"annotations":{"version/config": "20190411" }}}}}'
这个例子里我们在 .spec.template.metadata.annotations 中添加 version/config ,每次通过修改 version/config 来触发滚动更新
!!! 更新 ConfigMap 后:
内容来自
转载地址:http://llkof.baihongyu.com/