K8S之存储ConfigMap概述与说明，并详解常用ConfigMap示例

主机配置规划

ConfigMap概述

ConfigMap 是一种 API 对象，用来将非机密性的数据保存到健值对中。使用时可以用作环境变量、命令行参数或者存储卷中的配置文件。

ConfigMap 将环境配置信息和容器镜像解耦，便于应用配置的修改。当你需要储存机密信息时可以使用 Secret 对象。

备注：ConfigMap 并不提供保密或者加密功能。如果你想存储的数据是机密的，请使用 Secret；或者使用其他第三方工具来保证数据的私密性，而不是用 ConfigMap。

ConfigMap创建方式

通过目录创建

配置文件目录

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# ll /root/k8s_practice/storage/configmap    # 配置文件存在哪个目录下4 total 8
5 -rw-r--r-- 1 root root 159 Jun  7 14:52game.properties6 -rw-r--r-- 1 root root  83 Jun  7 14:53ui.properties7 [root@k8s-master storage]#8 [root@k8s-master storage]# cat configmap/game.properties    # 涉及文件19 enemies=aliens10 lives=3
11 enemies.cheat=true
12 enemies.cheat.level=noGoodRotten13 secret.code.passphrase=UUDDLRLRBABAs14 secret.code.allowed=true
15 secret.code.lives=30
16 
17 [root@k8s-master storage]#18 [root@k8s-master storage]# cat configmap/ui.properties   # 涉及文件219 color.good=purple20 color.bad=yellow21 allow.textmode=true
22 how.nice.to.look=fairlyNice

创建ConfigMap并查看状态

1 [root@k8s-master storage]# kubectl create configmap game-config --from-file=/root/k8s_practice/storage/configmap2 configmap/game-config created3 [root@k8s-master storage]#4 [root@k8s-master storage]# kubectl get configmap5 NAME          DATA   AGE6 game-config   2      14s

查看ConfigMap有哪些数据

1 [root@k8s-master storage]# kubectl get configmap -o yaml   ##### 查看方式12 apiVersion: v13 items:4 -apiVersion: v15 data:6     game.properties: |+   ##### 本段最后有一行空格，+表示保留字符串行末尾的换行7       enemies=aliens8       lives=3
9       enemies.cheat=true
10       enemies.cheat.level=noGoodRotten11       secret.code.passphrase=UUDDLRLRBABAs12       secret.code.allowed=true
13       secret.code.lives=30
14 
15     ui.properties: |
16       color.good=purple17       color.bad=yellow18       allow.textmode=true
19       how.nice.to.look=fairlyNice20 kind: ConfigMap21 metadata:22     creationTimestamp: "2020-06-07T06:57:28Z"
23     name: game-config24 namespace: default25     resourceVersion: "889177"
26     selfLink: /api/v1/namespaces/default/configmaps/game-config27     uid: 6952ac85-ded0-4c5e-89fd-b0c6f0546ecf28 kind: List29 metadata:30   resourceVersion: ""
31   selfLink: ""
32 [root@k8s-master storage]#33 [root@k8s-master storage]# kubectl describe configmap game-config   ##### 查看方式234 Name:         game-config35 Namespace:    default36 Labels:       
37 Annotations:  
38 
39 Data40 ====
41 game.properties:42 ----
43 enemies=aliens44 lives=3
45 enemies.cheat=true
46 enemies.cheat.level=noGoodRotten47 secret.code.passphrase=UUDDLRLRBABAs48 secret.code.allowed=true
49 secret.code.lives=30
50 
51 
52 ui.properties:53 ----
54 color.good=purple55 color.bad=yellow56 allow.textmode=true
57 how.nice.to.look=fairlyNice58 
59 Events:  

通过文件创建

配置文件位置

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# cat /root/k8s_practice/storage/configmap/game.properties4 enemies=aliens5 lives=3
6 enemies.cheat=true
7 enemies.cheat.level=noGoodRotten8 secret.code.passphrase=UUDDLRLRBABAs9 secret.code.allowed=true
10 secret.code.lives=30

创建ConfigMap并查看状态

1 [root@k8s-master storage]# kubectl create configmap game-config-2 --from-file=/root/k8s_practice/storage/configmap/game.properties2 configmap/game-config-2created3 [root@k8s-master storage]#4 [root@k8s-master storage]# kubectl get configmap game-config-2
5 NAME            DATA   AGE6 game-config-2   1      29s

查看ConfigMap有哪些数据

1 [root@k8s-master storage]# kubectl get configmap game-config-2 -o yaml   ##### 查看方式12 apiVersion: v13 data:4   game.properties: |+   ##### 本段最后有一行空格，+表示保留字符串行末尾的换行5     enemies=aliens6     lives=3
7     enemies.cheat=true
8     enemies.cheat.level=noGoodRotten9     secret.code.passphrase=UUDDLRLRBABAs10     secret.code.allowed=true
11     secret.code.lives=30
12 
13 kind: ConfigMap14 metadata:15   creationTimestamp: "2020-06-07T07:05:47Z"
16   name: game-config-2
17 namespace: default18   resourceVersion: "890437"
19   selfLink: /api/v1/namespaces/default/configmaps/game-config-2
20   uid: 02d99802-c23f-45ad-b4e1-dea9bcb166d821 [root@k8s-master storage]#22 [root@k8s-master storage]# kubectl describe configmap game-config-2##### 查看方式223 Name:         game-config-2
24 Namespace:    default25 Labels:       
26 Annotations:  
27 
28 Data29 ====
30 game.properties:31 ----
32 enemies=aliens33 lives=3
34 enemies.cheat=true
35 enemies.cheat.level=noGoodRotten36 secret.code.passphrase=UUDDLRLRBABAs37 secret.code.allowed=true
38 secret.code.lives=30
39 
40 
41 Events:  

通过命令行创建

创建ConfigMap并查看状态

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# kubectl create configmap special-config --from-literal=special.how=very --from-literal="special.type=charm"
4 configmap/special-config created5 [root@k8s-master storage]#6 [root@k8s-master storage]# kubectl get configmap special-config7 NAME             DATA   AGE8 special-config   2      23s

查看ConfigMap有哪些数据

1 [root@k8s-master storage]# kubectl get configmap special-config -o yaml    ##### 查看方式12 apiVersion: v13 data:4 special.how: very5 special.type: charm6 kind: ConfigMap7 metadata:8   creationTimestamp: "2020-06-07T09:32:04Z"
9   name: special-config10 namespace: default11   resourceVersion: "912702"
12   selfLink: /api/v1/namespaces/default/configmaps/special-config13   uid: 76698e78-1380-4826-b5ac-d9c81f746eac14 [root@k8s-master storage]#15 [root@k8s-master storage]# kubectl describe configmap special-config    ##### 查看方式216 Name:         special-config17 Namespace:    default18 Labels:       
19 Annotations:  
20 
21 Data22 ====
23 special.how:24 ----
25 very26 special.type:27 ----
28 charm29 Events:  

通过yaml文件创建

yaml文件

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# catconfigmap.yaml4 apiVersion: v15 kind: ConfigMap6 metadata:7   name: configmap-demo8 data:9 # 类属性键；每一个键都映射到一个简单的值10   player_initial_lives: "3"
11   ui_properties_file_name: 'user-interface.properties'
12 #13 # 类文件键14   game.properties: |
15     enemy.types=aliens,monsters16     player.maximum-lives=5
17   user-interface.properties: |
18     color.good=purple19     color.bad=yellow20     allow.textmode=true

创建ConfigMap并查看状态

1 [root@k8s-master storage]# kubectl apply -f configmap.yaml2 configmap/configmap-demo created3 [root@k8s-master storage]# kubectl get configmap configmap-demo4 NAME             DATA   AGE5 configmap-demo   4      2m59s

查看ConfigMap有哪些数据

1 [root@k8s-master storage]# kubectl get configmap configmap-demo -o yaml    ##### 查看方式12 apiVersion: v13 data:4   game.properties: |
5     enemy.types=aliens,monsters6     player.maximum-lives=5
7   player_initial_lives: "3"
8   ui_properties_file_name: user-interface.properties9   user-interface.properties: |
10     color.good=purple11     color.bad=yellow12     allow.textmode=true
13 kind: ConfigMap14 metadata:15 annotations:16     kubectl.kubernetes.io/last-applied-configuration: |
17       {"apiVersion":"v1","data":{"game.properties":"enemy.types=aliens,monsters\nplayer.maximum-lives=5\n","player_initial_lives":"3","ui_properties_file_name":"user-interface.properties","user-interface.properties":"color.good=purple\ncolor.bad=yellow\nallow.textmode=true\n"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"configmap-demo","namespace":"default"}}18   creationTimestamp: "2020-06-07T11:36:46Z"
19   name: configmap-demo20 namespace: default21   resourceVersion: "931685"
22   selfLink: /api/v1/namespaces/default/configmaps/configmap-demo23   uid: fdad7000-87bd-4b72-be98-40dd8fe6400a24 [root@k8s-master storage]#25 [root@k8s-master storage]#26 [root@k8s-master storage]# kubectl describe configmap configmap-demo     ##### 查看方式227 Name:         configmap-demo28 Namespace:    default29 Labels:       
30 Annotations:  kubectl.kubernetes.io/last-applied-configuration:31                 {"apiVersion":"v1","data":{"game.properties":"enemy.types=aliens,monsters\nplayer.maximum-lives=5\n","player_initial_lives":"3","ui_proper...
32 
33 Data34 ====
35 game.properties:36 ----
37 enemy.types=aliens,monsters38 player.maximum-lives=5
39 
40 player_initial_lives:41 ----
42 3
43 ui_properties_file_name:44 ----
45 user-interface.properties46 user-interface.properties:47 ----
48 color.good=purple49 color.bad=yellow50 allow.textmode=true
51 
52 Events:  

Pod中使用ConfigMap

如何在Pod中使用上述的ConfigMap信息。

当前存在的ConfigMap

1 [root@k8s-master storage]# kubectl get configmap2 NAME             DATA   AGE3 configmap-demo   430m4 game-config      25h9m5 game-config-2    15h1m6 special-config   2      5m48s

使用ConfigMap来替代环境变量

yaml文件

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# catpod_configmap_env.yaml4 apiVersion: v15 kind: Pod6 metadata:7   name: pod-configmap-env
8 spec:9 containers:10   -name: myapp11     image: registry.cn-beijing.aliyuncs.com/google_registry/myapp:v112     command: ["/bin/sh", "-c", "env"]13 ### 引用方式114     env:15     -name: SPECAIL_HOW_KEY16 valueFrom:17 configMapKeyRef:18           name: special-config   ### 这个name的值来自 ConfigMap19 key: special.how       ### 这个key的值为需要取值的键20     -name: SPECAIL_TPYE_KEY21 valueFrom:22 configMapKeyRef:23           name: special-config24 key: special.type25 ### 引用方式226 envFrom:27     -configMapRef:28         name: game-config-2### 这个name的值来自 ConfigMap29     restartPolicy: Never

启动pod并查看状态

1 [root@k8s-master storage]# kubectl apply -f pod_configmap_env.yaml2 pod/pod-configmap-envcreated3 [root@k8s-master storage]#4 [root@k8s-master storage]# kubectl get pod -o wide5 NAME                READY   STATUS      RESTARTS   AGE   IP             NODE         NOMINATED NODE   READINESS GATES6 pod-configmap-env   0/1     Completed   0          6s    10.244.2.147   k8s-node02              

查看打印日志

1 [root@k8s-master storage]# kubectl logs pod-configmap-env 
2 MYAPP_SVC_PORT_80_TCP_ADDR=10.98.57.156
3 KUBERNETES_SERVICE_PORT=443
4 KUBERNETES_PORT=tcp://10.96.0.1:443
5 MYAPP_SVC_PORT_80_TCP_PORT=80
6 HOSTNAME=pod-configmap-env
7 SHLVL=1
8 MYAPP_SVC_PORT_80_TCP_PROTO=tcp9 HOME=/root10 SPECAIL_HOW_KEY=very  ### 来自ConfigMap11 game.properties=enemies=aliens  ### 来自ConfigMap12 lives=3### 来自ConfigMap13 enemies.cheat=true### 来自ConfigMap14 enemies.cheat.level=noGoodRotten  ### 来自ConfigMap15 secret.code.passphrase=UUDDLRLRBABAs  ### 来自ConfigMap16 secret.code.allowed=true### 来自ConfigMap17 secret.code.lives=30### 来自ConfigMap18 
19 
20 SPECAIL_TPYE_KEY=charm  ### 来自ConfigMap21 MYAPP_SVC_PORT_80_TCP=tcp://10.98.57.156:80
22 NGINX_VERSION=1.12.2
23 KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
24 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin25 KUBERNETES_PORT_443_TCP_PORT=443
26 KUBERNETES_PORT_443_TCP_PROTO=tcp27 MYAPP_SVC_SERVICE_HOST=10.98.57.156
28 KUBERNETES_SERVICE_PORT_HTTPS=443
29 KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
30 PWD=/
31 KUBERNETES_SERVICE_HOST=10.96.0.1
32 MYAPP_SVC_SERVICE_PORT=80
33 MYAPP_SVC_PORT=tcp://10.98.57.156:80

使用ConfigMap设置命令行参数

yaml文件

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# catpod_configmap_cmd.yaml4 apiVersion: v15 kind: Pod6 metadata:7   name: pod-configmap-cmd8 spec:9 containers:10   -name: myapp11     image: registry.cn-beijing.aliyuncs.com/google_registry/myapp:v112     command: ["/bin/sh", "-c", "echo \"===$(SPECAIL_HOW_KEY)===$(SPECAIL_TPYE_KEY)===\""]13     env:14     -name: SPECAIL_HOW_KEY15 valueFrom:16 configMapKeyRef:17           name: special-config18 key: special.how19     -name: SPECAIL_TPYE_KEY20 valueFrom:21 configMapKeyRef:22           name: special-config23 key: special.type24   restartPolicy: Never

启动pod并查看状态

1 [root@k8s-master storage]# kubectl apply -f pod_configmap_cmd.yaml2 pod/pod-configmap-cmd created3 [root@k8s-master storage]#4 [root@k8s-master storage]# kubectl get pod -o wide5 NAME                READY   STATUS      RESTARTS   AGE   IP             NODE         NOMINATED NODE   READINESS GATES6 pod-configmap-cmd   0/1     Completed   0          5s    10.244.4.125   k8s-node01              

查看打印日志

1 [root@k8s-master storage]# kubectl logs pod-configmap-cmd2 ===very===charm===

通过数据卷插件使用ConfigMap【推荐】

在数据卷里面使用ConfigMap，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【第一层级的键】，键值就是文件内容。

yaml文件

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# catpod_configmap_volume.yaml4 apiVersion: v15 kind: Pod6 metadata:7   name: pod-configmap-volume8 spec:9 containers:10   -name: myapp11     image: registry.cn-beijing.aliyuncs.com/google_registry/myapp:v112     #command: ["/bin/sh", "-c", "ls -l /etc/config/"]13     command: ["/bin/sh", "-c", "sleep 600"]14 volumeMounts:15     - name: config-volume16       mountPath: /etc/config17 volumes:18   - name: config-volume19 configMap:20       name: configmap-demo21   restartPolicy: Never

启动pod并查看状态

1 [root@k8s-master storage]# kubectl apply -f pod_configmap_volume.yaml2 pod/pod-configmap-volume created3 [root@k8s-master storage]#4 [root@k8s-master storage]# kubectl get pod -o wide5 NAME                   READY   STATUS    RESTARTS   AGE   IP             NODE         NOMINATED NODE   READINESS GATES6 pod-configmap-volume   1/1     Running   0          5s    10.244.2.153   k8s-node02              

进入pod并查看

1 [root@k8s-master storage]# kubectl exec -it pod-configmap-volume sh
2 / # ls /etc/config3 game.properties            player_initial_lives       ui_properties_file_name    user-interface.properties4 /#5 /#6 /#7 / # cat /etc/config/player_initial_lives8 3/#9 /#10 /#11 / # cat /etc/config/ui_properties_file_name12 user-interface.properties/#13 /#14 /#15 / # cat /etc/config/game.properties16 enemy.types=aliens,monsters17 player.maximum-lives=5
18 /#19 /#20 / # cat /etc/config/user-interface.properties21 color.good=purple22 color.bad=yellow23 allow.textmode=true

ConfigMap热更新

准备工作

yaml文件

1 [root@k8s-master storage]# pwd
2 /root/k8s_practice/storage3 [root@k8s-master storage]# catpod_configmap_hot.yaml4 apiVersion: v15 kind: ConfigMap6 metadata:7   name: log-config8 namespace: default9 data:10 log_level: INFO11 ---
12 apiVersion: apps/v113 kind: Deployment14 metadata:15   name: myapp-deploy16 namespace: default17 spec:18   replicas: 2
19 selector:20 matchLabels:21 app: myapp22 release: v123 template:24 metadata:25 labels:26 app: myapp27 release: v128         env: test29 spec:30 containers:31       -name: myapp32         image: registry.cn-beijing.aliyuncs.com/google_registry/myapp:v133 imagePullPolicy: IfNotPresent34 ports:35         - containerPort: 80
36 volumeMounts:37         - name: config-volume38           mountPath: /etc/config39 volumes:40       - name: config-volume41 configMap:42           name: log-config

应用yaml文件并查看状态

1 [root@k8s-master storage]# kubectl apply -f pod_configmap_hot.yaml2 configmap/log-config created3 deployment.apps/myapp-deploy created4 [root@k8s-master storage]#5 [root@k8s-master storage]# kubectl get configmap log-config6 NAME         DATA   AGE7 log-config   121s8 [root@k8s-master storage]#9 [root@k8s-master storage]# kubectl get pod -o wide10 NAME                           READY   STATUS    RESTARTS   AGE   IP             NODE         NOMINATED NODE   READINESS GATES11 myapp-deploy-58ff9c997-drhwk   1/1     Running   0          30s   10.244.2.154   k8s-node02              
12 myapp-deploy-58ff9c997-n68j2   1/1     Running   0          30s   10.244.4.126   k8s-node01              

查看ConfigMap信息

1 [root@k8s-master storage]# kubectl get configmap log-config -o yaml2 apiVersion: v13 data:4 log_level: INFO5 kind: ConfigMap6 metadata:7 annotations:8     kubectl.kubernetes.io/last-applied-configuration: |
9       {"apiVersion":"v1","data":{"log_level":"INFO"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"log-config","namespace":"default"}}10   creationTimestamp: "2020-06-07T16:08:11Z"
11   name: log-config12 namespace: default13   resourceVersion: "971348"
14   selfLink: /api/v1/namespaces/default/configmaps/log-config15   uid: 7e78e1d7-12de-4601-9915-cefbc96ca305

查看pod中的ConfigMap信息

1 [root@k8s-master storage]# kubectl exec -it myapp-deploy-58ff9c997-drhwk -- cat /etc/config/log_level2 INFO

热更新

修改ConfigMap

1 [root@k8s-master storage]# kubectl edit configmap log-config     ### 将 INFO 改为了 DEBUG2 # Please edit the object below. Lines beginning with a '#'will be ignored,3 # and an empty file will abort the edit. If an error occurs while saving this filewill be4 # reopened with the relevant failures.5 #6 apiVersion: v17 data:8 log_level: DEBUG9 kind: ConfigMap10 metadata:11 annotations:12     kubectl.kubernetes.io/last-applied-configuration: |
13       {"apiVersion":"v1","data":{"log_level":"DEBUG"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"log-config","namespace":"default"}}14   creationTimestamp: "2020-06-07T16:08:11Z"
15   name: log-config16 namespace: default17   resourceVersion: "971348"
18   selfLink: /api/v1/namespaces/default/configmaps/log-config19   uid: 7e78e1d7-12de-4601-9915-cefbc96ca305

查看ConfigMap信息

1 [root@k8s-master storage]# kubectl get configmap log-config -o yaml2 apiVersion: v13 data:4 log_level: DEBUG5 kind: ConfigMap6 metadata:7 annotations:8     kubectl.kubernetes.io/last-applied-configuration: |
9       {"apiVersion":"v1","data":{"log_level":"DEBUG"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"log-config","namespace":"default"}}10   creationTimestamp: "2020-06-07T16:08:11Z"
11   name: log-config12 namespace: default13   resourceVersion: "972893"
14   selfLink: /api/v1/namespaces/default/configmaps/log-config15   uid: 7e78e1d7-12de-4601-9915-cefbc96ca305

稍后10秒左右，再次查看pod中的ConfigMap信息

1 [root@k8s-master storage]# kubectl exec -it myapp-deploy-58ff9c997-drhwk -- cat /etc/config/log_level2 DEBUG

由此可见，完成了一次热更新

相关阅读

1、YAML 语言教程与使用案例

2、Kubernetes K8S之通过yaml创建pod与pod文件常用字段详解

3、Kubernetes K8S之存储Secret详解

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