ConfigMap
作者：互联网
configMap 描述信息
ConfigMap是一种API对象，用来将非加密数据保存到键值对中。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可以将环境变量配置信息和容器镜像解耦，便于应用配置的修改。如果需要存储加密信息时可以使用Secret对象。
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
作用就是存储配置信息！
ConfigMap 的创建
使用目录创建
ls docs/user-guide/configmap/kubectl/
game.properties
ui.properties
$ cat docs/user-guide/configmap/kubectl/game.properties
enemies=aliens
lives=3
enemies.cheat=true
enemies.cheat.level=noGoodRotten
secret.code.passphrase=UUDDLRLRBABAS
secret.code.allowed=true
secret.code.lives=30
$ cat docs/user-guide/configmap/kubectl/ui.properties
color.good=purple
color.bad=yellow
allow.textmode=true
how.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
[root@k8s-master01 ~]# pwd
/root
[root@k8s-master01 ~]# mkdir configmap
[root@k8s-master01 ~]# cd configmap/
[root@k8s-master01 configmap]# mkdir dir
[root@k8s-master01 configmap]# cd dir/
[root@k8s-master01 dir]# vim game.properties
[root@k8s-master01 dir]# vim ui.properties
[root@k8s-master01 dir]# kubectl create configmap game-config --from-file=../dir
configmap/game-config created
[root@k8s-master01 dir]# kubectl get cm
NAME DATA AGE
game-config 2 11s
kube-root-ca.crt 1 10d
[root@k8s-master01 dir]# kubectl get cm game-config -o yaml
apiVersion: v1
data:
game.properties: |
enemies=aliens
lives=3
enemies.cheat=true
enemies.cheat.level=noGoodRotten
secret.code.passphrase=UUDDLRLRBABAS
secret.code.allowed=true
secret.code.lives=30
ui.properties: |
color.good=purple
color.bad=yellow
allow.textmode=true
how.nice.to.look=fairlyNice
kind: ConfigMap
metadata:
creationTimestamp: "2022-07-13T02:22:15Z"
name: game-config
namespace: default
resourceVersion: "57642"
uid: 64e4024d-92e8-4f83-acb0-ad3d2716b65f
[root@k8s-master01 dir]# kubectl describe cm game-config
Name: game-config
Namespace: default
Labels: <none>
Annotations: <none>
Data
====
game.properties:
----
enemies=aliens
lives=3
enemies.cheat=true
enemies.cheat.level=noGoodRotten
secret.code.passphrase=UUDDLRLRBABAS
secret.code.allowed=true
secret.code.lives=30
ui.properties:
----
color.good=purple
color.bad=yellow
allow.textmode=true
how.nice.to.look=fairlyNice
BinaryData
====
Events: <none>
使用文件创建
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/user•guide/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
[root@k8s-master01 dir]# kubectl create configmap game-config-2 --from-file=game.properties
configmap/game-config-2 created
[root@k8s-master01 dir]# kubectl get cm
NAME DATA AGE
game-config 2 7m56s
game-config-2 1 7s
kube-root-ca.crt 1 10d
[root@k8s-master01 dir]# kubectl describe cm game-config-2
Name: game-config-2
Namespace: default
Labels: <none>
Annotations: <none>
Data
====
game.properties:（键名）
----
enemies=aliens（键值）
lives=3
enemies.cheat=true
enemies.cheat.level=noGoodRotten
secret.code.passphrase=UUDDLRLRBABAS
secret.code.allowed=true
secret.code.lives=30
BinaryData
====
Events: <none>
[root@k8s-master01 dir]#
使用字面值创建
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 --from-literal=special.type=charm
$ kubectl get configmaps special-config -o yaml
[root@k8s-master01 dir]# kubectl create configmap special-config --from-literal=special.how=very --from-literal=special.type=charm
configmap/special-config created
[root@k8s-master01 dir]# kubectl describe cm special-config
Name: special-config
Namespace: default
Labels: <none>
Annotations: <none>
Data
====
special.how:（键名）
----
very （键值）
special.type:（键名）
----
charm （键值）
BinaryData
====
Events: <none>
[root@k8s-master01 dir]#
Pod 中使用 ConfigMap
使用 ConfigMap 来替代环境变量
1、
apiVersion: v1
kind: ConfigMap
metadata:
name: special-config
namespace: default
data:
special.how: very
special.type: charm
[root@k8s-master01 env]# kubectl get cm
NAME DATA AGE
game-config 2 17m
game-config-2 1 10m
kube-root-ca.crt 1 10d
special-config 2 5m51s
2、
apiVersion: v1
kind: ConfigMap
metadata:
name: env-config
namespace: default
data:
log_level: INFO
root@k8s-master01 configmap]# pwd
/root/configmap
[root@k8s-master01 configmap]# ls
dir
[root@k8s-master01 configmap]# mkdir env
[root@k8s-master01 configmap]# cd env/
[root@k8s-master01 env]# vim env.yaml
[root@k8s-master01 env]# kubectl apply -f env.yaml
configmap/env-config created
[root@k8s-master01 env]# kubectl get cm
NAME DATA AGE
env-config 1 9s
game-config 2 17m
game-config-2 1 10m
kube-root-ca.crt 1 10d
special-config 2 5m51s
[root@k8s-master01 env]#
3、
apiVersion: v1
kind: Pod
metadata:
name: dapi-test-pod
spec:
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
[root@k8s-master01 env]# vim pod.yaml
[root@k8s-master01 env]# kubectl create -f pod.yaml
pod/dapi-test-pod created
[root@k8s-master01 env]# kubectl get pod
NAME READY STATUS RESTARTS AGE
dapi-test-pod 0/1 Completed 0 3s
[root@k8s-master01 env]#
[root@k8s-master01 env]# kubectl logs dapi-test-pod
KUBERNETES_PORT=tcp://10.96.0.1:443
KUBERNETES_SERVICE_PORT=443
HOSTNAME=dapi-test-pod
HOME=/root
PKG_RELEASE=1~bullseye
SPECIAL_TYPE_KEY=charm
KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
NGINX_VERSION=1.21.5
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
KUBERNETES_PORT_443_TCP_PORT=443
NJS_VERSION=0.7.1
KUBERNETES_PORT_443_TCP_PROTO=tcp
SPECIAL_LEVEL_KEY=very
log_level=INFO
KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
KUBERNETES_SERVICE_PORT_HTTPS=443
KUBERNETES_SERVICE_HOST=10.96.0.1
PWD=/
[root@k8s-master01 env]#
这个就是通过configmap把环境变量注入到pod内部
用 ConfigMap 设置命令行参数
apiVersion: v1
kind: ConfigMap
metadata:
name: special-config
namespace: default
data:
special.how: very
special.type: charm
apiVersion: v1
kind: Pod
metadata:
name: dapi-test-pod
spec:
containers:
- name: test-container
image: nginx
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
[root@k8s-master01 env]# vim pod1.yaml
[root@k8s-master01 env]# kubectl create -f pod1.yaml
pod/dapi-test-pod66 created
[root@k8s-master01 env]# kubectl get pod
NAME READY STATUS RESTARTS AGE
dapi-test-pod 0/1 Completed 0 8m37s
dapi-test-pod66 0/1 Completed 0 10s
[root@k8s-master01 env]# kubectl logs dapi-test-pod66
very charm
[root@k8s-master01 env]#
通过数据卷插件使用ConfigMap
apiVersion: v1
kind: ConfigMap
metadata:
name: special-config
namespace: default
data:
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: v1
kind: Pod
metadata:
name: dapi-test-pod
spec:
containers:
- name: test-container
image: nginx
command: [ "/bin/sh", "-c", "sleep 600s" ]
volumeMounts:
- name: config-volume
mountPath: /etc/config
volumes:
- name: config-volume
configMap:
name: special-config
restartPolicy: Never
[root@k8s-master01 env]# vim 111.yaml
[root@k8s-master01 env]# kubectl apply -f 111.yaml
pod/dapi-test-pod11 created
[root@k8s-master01 env]# kubectl get pod
NAME READY STATUS RESTARTS AGE
dapi-test-pod 0/1 Completed 0 16m
dapi-test-pod11 1/1 Running 0 26s
dapi-test-pod66 0/1 Completed 0 8m28s
[root@k8s-master01 env]#
[root@k8s-master01 env]# kubectl exec dapi-test-pod11 -it -- /bin/sh
# cd /etc/config
# ls
special.how special.type
# cat special.how
very# cat special.type
charm#
ConfigMap 的热更新
apiVersion: v1
kind: ConfigMap
metadata:
name: log-config
namespace: default
data:
log_level: INFO
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: my-nginx
spec:
replicas: 1
template:
metadata:
labels:
run: my-nginx
spec:
containers:
- name: my-nginx
image: nginx
ports:
- containerPort: 80
volumeMounts:
- name: config-volume
mountPath: /etc/config
volumes:
- name: config-volume
configMap:
name: log-config
[root@k8s-master01 config]# kubectl apply -f 111.yaml
configmap/log-config created
The Deployment "my-nginx" is invalid: spec.template.metadata.labels: Invalid value: map[string]string{"run":"my-nginx"}: `selector` does not match template `labels`
（这里会报错！）
[root@k8s-master01 config]# kubectl apply -f 111.yaml
configmap/log-config unchanged
deployment.apps/my-nginx created
[root@k8s-master01 config]#
[root@k8s-master01 config]# kubectl get pod
NAME READY STATUS RESTARTS AGE
my-nginx-6cc567cbd6-fg4t8 1/1 Running 0 2m10s
[root@k8s-master01 config]# kubectl exec my-nginx-6cc567cbd6-fg4t8 -it -- cat /etc/config/log_level
INFO[root@k8s-master01 config]#
（kubectl exec kubectl get pods -l run=my-nginx -o=name|cut -d "/" -f2 cat/etc/config/log_levelINFO）
修改 ConfigMap
[root@k8s-master01 config]# kubectl edit configmap log-config
configmap/log-config edited
修改 log_level 的值为 DEBUG
[root@k8s-master01 config]# kubectl exec my-nginx-6cc567cbd6-fg4t8 -it -- cat /etc/config/log_level
DEBUG
[root@k8s-master01 config]#
理解：
我们刚刚进入修改confimap，pod的内容已经发生了变化。如果这个是nginx的配置文件，这样的话说明已经达到了热更新的目的了！
（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
kubectl patch deployment my-nginx --patch '{"spec": {"template": {"metadata": {"annotations":{"version/config": "20190411" }}}}}'（修改时间）
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：
-
使用该 ConfigMap 挂载的 Env 不会同步更新
-
使用该 ConfigMap 挂载的 Volume 中的数据需要一段时间（实测大概10秒）才能同步更新
标签：ConfigMap,kubectl,root,master01,k8s,config,special 来源： https://www.cnblogs.com/zypdbk/p/16473335.html