kubernetes的配置管理configmap管理

配置管理

配置介绍

生产中的应用程序，一般都会涉及到配置文件，而配置文件经常会有变更，比如: 数据库连接,代码版本号,证书更新等

典型场景：
项目经历开发环境、测试环境、预发布环境、线上环境才能完成发布，而每个环境都有定义其独立的各
种配置，这些配置手工操作很繁杂，一些流行的开源项目,比如: Nacos,Consul,Apollo等可以实现配置管
理, 还有大公司专门开发了专用配置管理中心，如百度的disconf等。但通常此方法需要开发者参与，通
过开发者写代码实现调用，并且和某种开发语言深度绑定
在容器化大行其道的当前，在为容器化应用提供配置信息方法一般有下面方法

制作镜像时，提前将定义好的配置文件拷贝进镜像之中
制作镜像时，内置环境变量，在启动容器时通过环境变量向容器传递配置数据，容器启动后将无法传递新的变量
启动容器时，基于存储卷向容器传递配置文件,但需要提前准备外部的存储
启动容器时，传递自定义的启动的命令，选项，参数

kubernetes作为分布式容器调度平台，同样会遇到配置变更的问题，如果将资源删除，重新修改配置再重新创建，这种方法太繁琐。
kubernetes提供了对 Pod 容器应用可以实现集中式的配置管理功能的相关资源：

ConfigMap
Secret
downwardAPI
Projected

通过这些组件来实现向pod中的容器应用中注入配置信息的机制，从而避免了开发者参与
注意：对于运行中容器的配置改变，还需要通过应用程序重载相关配置才能生效

配置组件简介

https://kubernetes.io/zh-cn/docs/concepts/configuration/

Configmap
Configmap是Kubernetes集群中非常重要的一种配置管理资源对象。
借助于ConfigMap API可以向pod中的容器中注入配置信息。
ConfigMap不仅可以保存环境变量或命令行参数等属性，也可以用来保存整个配置文件或者JSON格式的文件。
各种配置属性和数据以 k/v或嵌套k/v 样式存在到Configmap中
注意：所有的配置信息都是以明文的方式来进行保存，实现资源配置的快速获取或者更新。

Secret
Kubernetes集群中，有一些配置属性信息是非常敏感的，所以这些信息在传递的过程中，是不希望其他人能够看到的
Kubernetes提供了一种加密场景中的配置管理资源对象Secret。
它在进行数据传输之前，会对数据进行编码，在数据获取的时候，会对数据进行解码。从而保证整个数据传输过程的安全。
注意：这些数据通常采用Base64机制保存，所以安全性一般

DownwardAPI
downwardAPI 为运行在pod中的应用容器提供了一种反向引用。让容器中的应用程序了解所处pod或
Node的一些基础外部属性信息。
从严格意义上来说，downwardAPI不是存储卷，它自身就存在。
相较于configmap、secret等资源对象需要创建后才能使用，而downwardAPI引用的是Pod自身的运行
环境信息，这些信息在Pod启动的时候就存在。

Projected
一个 projected Volumes 投射卷可以将若干现有的卷源映射到容器内的同一个目录之上。

应用的配置

环境变量 $remote_addr
配置文件

configmap

表现为Pod
1）环境变量
2）配置文件

ConfigMap

ConfigMap 说明

https://kubernetes.io/zh-cn/docs/concepts/configuration/configmap/
https://kubernetes.io/zh-cn/docs/tasks/configure-pod-container/configure-podconfigmap/

Kubernetes提供了对pod中容器应用的集中配置管理组件：ConfigMap。
通过ConfigMap来实现向pod中的容器中注入配置信息的机制。

可以把configmap理解为Linux系统中的/etc目录，专门用来存储配置文件的目录
Kubernetes借助于ConfigMap对象实现了将配置信息从容器镜像中解耦，从而增强了工作负载的可移樟
性、使其配置更易于更改和管理并避免了将配置数据硬编码到Pod配置清单中
ConfigMap不仅仅可以保存单个属性，也可以用来保存整个配置文件。
虽然configmap可以对各种应用程序提供定制配置服务，但是一般不用它来替代专门的配置文件，
从Kubernetes v1.19版本开始，ConfigMap和Secret支持使用immutable字段创建不可变实例，实现不
可变基础设施效果
注意: Configmap 属于名称空间级别,只能被同一个名称空间的Pod引用

#环境变量
kubectl explain pod.spec.containers.env.valueFrom
#配置文件
kubectl explain pod.spec.volumes.configMap

基本属性

#kubectl explain cm
   binaryData #二进制数据
   data   #文本数据，支持变量和文件
   immutable <boolean>  #设为true，不能被修改只能删除，默认为nil可以随时被修改
#注意：基于data的方式传递信息的话，会在pod的容器内部生成一个单独的数据文件

命令行创建方式案例

范例：命令行创建基于key/value形式的变

kubectl create configmap cm-test1 --from-literal=key1='value1' --from-literal=key2='value2'

[root@master1 sc-nfs]# kubectl get cm
NAME               DATA   AGE
cm-test1           2      7s
envoy-config       1      10d
kube-root-ca.crt   1      14d

root@master1 sc-nfs]# kubectl get cm cm-test1 -o yaml
apiVersion: v1
data:
  key1: value1
  key2: value2
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T09:07:03Z"
  name: cm-test1
  namespace: default
  resourceVersion: "316769"
  uid: f650fe51-bdf6-44ea-b539-73996e641540

[root@master1 sc-nfs]# kubectl describe cm cm-test1
Name:         cm-test1
Namespace:    default
Labels:       <none>
Annotations:  <none>

Data
====
key1:
----
value1

key2:
----
value2


BinaryData
====

Events:  <none>

#删除CM

kubectl delete cm cm-test1

范例: 命令行创建基于key/value形式的变量配置

#创建CM

kubectl create configmap pod-test-config --from-literal=host="127.0.0.1" --from-literal=port="8888"

#验证创建成功

[root@master1 config]# kubectl get cm            
NAME               DATA   AGE
envoy-config       1      10d
kube-root-ca.crt   1      14d
pod-test-config    2      16s

#显示CM内容

root@master1 config]# kubectl get cm  pod-test-config -o yaml
apiVersion: v1
data:
  host: 127.0.0.1
  port: "8888"
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T09:17:49Z"
  name: pod-test-config
  namespace: default
  resourceVersion: "318069"
  uid: 66a0f215-6fb9-4213-8ee7-bd6a1ad4d2f1

#删除CM

kubectl delete cm pod-test-config

范例: 命令行创建基于环境变量文件的变量配置

#如果变量较多，使用上面方式一个个的设定环境变量太繁琐，可以全部添加到环境变量文件中然后基于它来创建CM。
#定制环境变量文件

[root@master1 config]# cat env
a=1
b=2
c=3

#注意：env文件中所有的配置项以 "属性名=属性值" 格式定制

#将所有环境变量添加到到configmap中

kubectl create configmap cm-test2 --from-env-file=env

[root@master1 config]# kubectl get cm cm-test2 -o yaml 
apiVersion: v1
data:
  a: "1"
  b: "2"
  c: "3"
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T09:33:47Z"
  name: cm-test2
  namespace: default
  resourceVersion: "319989"
  uid: 3ebb41cb-81c0-45ff-89b7-de9a2aaefc93

范例：命令行创建基于配置文件的文件形式CM

#直接将多个配置文件创建为一个ConfigMap

mkdir conf.d

[root@master1 conf.d]# ls
app1.conf  app2.conf  app3.conf

[root@master1 conf.d]# cat app1.conf
[app1]
config1

[root@master1 conf.d]# cat app2.conf
[app2]
config2

#文件名自动成为key名

kubectl create configmap cm-test3 --from-file=./conf.d/app1.conf --from-file=./conf.d/app2.conf

[root@master1 config]# kubectl get cm cm-test3 -o yaml
apiVersion: v1
data:
  app1.conf: |
    [app1]
    config1
  app2.conf: |
    [app2]
    config2
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T10:27:12Z"
  name: cm-test3
  namespace: default
  resourceVersion: "321196"
  uid: f581c47a-ee5b-4b76-ac61-6c43a3e6f832

范例: 命令行创建基于目录的CM

[root@master1 config]# ls conf.d/
app1.conf  app2.conf  app3.conf
[root@master1 config]#

[root@master1 ~]#cat conf.d/app1.conf
[app1]
config1
[root@master1 ~]#cat conf.d/app2.conf
[app2]
config2
[root@master1 ~]#cat conf.d/app3.conf
[app3]
config3

#直接将一个目录下的所有配置文件创建为一个ConfigMap

kubectl create configmap cm-test4 --from-file=./conf.d/

#结果显示：多个文件之间，属性名是文件名，属性值是文件内容

root@master1 config]# kubectl get cm cm-test4 -o yaml
apiVersion: v1
data:
  app1.conf: |
    [app1]
    config1
  app2.conf: |
    [app2]
    config2
  app3.conf: |
    [app3]
    config3
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T10:34:02Z"
  name: cm-test4
  namespace: default
  resourceVersion: "322014"
  uid: 04788ce7-fc65-412c-8432-cb3e681d771d

[root@master1 config]# cat nginx.conf

user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log notice;
pid        /var/run/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    keepalive_timeout  65;

    #gzip  on;

    include /etc/nginx/conf.d/*.conf;
}

kubectl create cm cm-nginx --from-file nginx.conf

kubectl get cm cm-nginx -o yaml

[root@master1 config]# kubectl get cm cm-nginx  -o yaml 
apiVersion: v1
data:
  nginx.conf: |2

    user  nginx;
    worker_processes  auto;

    error_log  /var/log/nginx/error.log notice;
    pid        /var/run/nginx.pid;


    events {
        worker_connections  1024;
    }


    http {
        include       /etc/nginx/mime.types;
        default_type  application/octet-stream;

        log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                          '$status $body_bytes_sent "$http_referer" '
                          '"$http_user_agent" "$http_x_forwarded_for"';

        access_log  /var/log/nginx/access.log  main;

        sendfile        on;
        #tcp_nopush     on;

        keepalive_timeout  65;

        #gzip  on;

        include /etc/nginx/conf.d/*.conf;
    }
kind: ConfigMap
metadata:
  creationTimestamp: "2026-05-24T10:41:25Z"
  name: cm-nginx
  namespace: default
  resourceVersion: "322902"
  uid: 895fd07d-5123-4ada-9700-0a770c9fba66

ConfigMap 使用
使用ConfigMap主要有两种方式：

通过环境变量的方式直接传递pod
使用volume的方式挂载入到pod内的文件中

注意：

ConfigMap必须在Pod之前创建
与ConfigMap在同一个namespace内的pod才能使用ConfigMap，即ConfigMap不能跨命名空间调用。
ConfigMap通常存放的数据不要超过1M
CM 可以支持实时更新，在原来的pod里面直接看到效果

通过环境变量的方式直接传递 Pod

引用ConfigMap对象上特定的key，以valueFrom赋值给Pod上指定的环境变量
也可以在Pod上使用envFrom一次性导入ConfigMap对象上的所有的key-value,key(可以统一附加特定前缀）即为环境变量,value自动成为相应的变量值
环境变量是容器启动时注入的，容器启动后变量的值不会随CM更改而发生变化,即一次性加载configmap,除非删除容器重建
通过环境变量脚本的方式，预处理这些配置信息
注意：环境变量的名称如果要用横线的话，最好使用下划线 _
环境变量格式

方式1：env 对指定的变量一个一个赋值

kubectl explain pod.spec.containers.env
 name #手工定制环境变量时，设置环境变量的名称，必选字段
 value #手工定制环境变量时，直接设置环境变量的属性值，不通过CM获取配置，可选字
段
 valueFrom #手工定制环境变量时，设置环境变量的属性来源，可以支持从
CM,Secret,downwordAPI获取
kubectl explain pod.spec.containers.env.valueFrom.configMapKeyRef
   name   #引用指定的configmap
   key   #引用指定的configmap中的具体哪个key
   optional #如果设置为false，标识该项是必选项，如果设置为true标识这个key是可选
的。默认false

#此方式实现过程
1）容器中自定义环境变量名
2）根据CM的名称和Key名，找到对应的value
3) 再将value赋值给容器的环境变量

ConfigMap 实战案例

范例：env 变量

#资源清单文件

[root@master1 config]# cat storage-configmap-simple-env.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: cm-nginx-config
data:
  port: "10086"  #注意:只支持字符串,需要用引号引起来
  user: "www"
---
apiVersion: v1
kind: Pod
metadata:
  name: configmap-env-test
spec:
  containers:
  - name: configmap-env-test
    image: registry.cn-beijing.aliyuncs.com/wangxiaochun/nginx:1.20.0
    env:
    - name: NGINX_HOST
      value: "10.0.0.100" #直接变量赋值
    - name: NGINX_PORT
      valueFrom:
        configMapKeyRef:
          name: cm-nginx-config
          key: port
          optional: true
    - name: NGINX_USER
      valueFrom:
        configMapKeyRef:
          name: cm-nginx-config
          key: user
          optional: false

optional: true 时这个变量有就有，没有都不会报错没有都不会报错

optional: false 时这个变量必须有，没有就报错

#配置解析：这里面我们可以使用两种方式在pod中传递变量

#资源创建

kubectl apply -f storage-configmap-simple-env.yaml

root@master1 config]# kubectl get cm
NAME               DATA   AGE
cm-nginx-config    2      27s
envoy-config       1      10d
kube-root-ca.crt   1      14d

[root@master1 config]# kubectl get pod
NAME                                        READY   STATUS    RESTARTS         AGE
configmap-env-test                          1/1     Running   0                92s
controller-deployment-demo-5f884bb8-2ppvf   1/1     Running   5 (3h57m ago)    44h
controller-deployment-demo-5f884bb8-fscrl   1/1     Running   14 (3h57m ago)   7d23h
controller-deployment-demo-5f884bb8-rfsbv   1/1     Running   13 (3h57m ago)   7d19h
[root@master1 config]#

[root@master1 config]# kubectl exec -it configmap-env-test -- env
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=configmap-env-test
TERM=xterm
NGINX_PORT=10086
NGINX_USER=www
NGINX_HOST=10.0.0.100
SERVICE_2_SERVICE_PORT=80
SERVICE_3_PORT_80_TCP=tcp://10.104.61.85:80
KUBERNETES_SERVICE_PORT_HTTPS=443
MYAPP_SERVICE_HOST=10.98.62.229
MYAPP_SERVICE_PORT=8080
MYAPP_PORT_8080_TCP_ADDR=10.98.62.229
SERVICE_2_PORT_80_TCP=tcp://10.98.59.151:80
SERVICE_3_PORT_80_TCP_PROTO=tcp
SERVICE_2_SERVICE_HOST=10.98.59.151
SERVICE_3_SERVICE_PORT=80
KUBERNETES_SERVICE_HOST=10.96.0.1
MYAPP_SERVICE_PORT_8080_80=8080
SERVICE_2_PORT=tcp://10.98.59.151:80
KUBERNETES_PORT=tcp://10.96.0.1:443
KUBERNETES_PORT_443_TCP_PROTO=tcp
MYAPP_PORT_8080_TCP_PORT=8080
SERVICE_2_PORT_80_TCP_PROTO=tcp
KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
SERVICE_2_PORT_80_TCP_ADDR=10.98.59.151
SERVICE_3_SERVICE_HOST=10.104.61.85
SERVICE_3_PORT=tcp://10.104.61.85:80
SERVICE_3_PORT_80_TCP_ADDR=10.104.61.85
KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
MYAPP_PORT_8080_TCP=tcp://10.98.62.229:8080
SERVICE_2_PORT_80_TCP_PORT=80
SERVICE_3_PORT_80_TCP_PORT=80
KUBERNETES_PORT_443_TCP_PORT=443
KUBERNETES_SERVICE_PORT=443
MYAPP_PORT=tcp://10.98.62.229:8080
MYAPP_PORT_8080_TCP_PROTO=tcp
NGINX_VERSION=1.20.0
NJS_VERSION=0.5.3
PKG_RELEASE=1~buster
HOME=/root

在线更新configmap 变量的值

kubectl edit cm cm-nginx-config

 Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  port: "10086"
  user: www
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"port":"10086","user":"www"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-nginx-config","namespace":"default"}
}
  creationTimestamp: "2026-05-24T11:07:34Z"
  name: cm-nginx-config
  namespace: default
  resourceVersion: "326043"

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  port: "9927"
  user: www
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"port":"10086","user":"www"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-nginx-config","namespace":"default"}
}
  creationTimestamp: "2026-05-24T11:07:34Z"

pod没有改变环境变量configmap修改了不会动态更新到pod 要把pod删了重建

[root@master1 config]# kubectl exec -it configmap-env-test -- env
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
HOSTNAME=configmap-env-test
TERM=xterm
NGINX_PORT=10086
NGINX_USER=www
NGINX_HOST=10.0.0.100
SERVICE_2_SERVICE_PORT=80
SERVICE_3_PORT_80_TCP=tcp://10.104.61.85:80
KUBERNETES_SERVICE_PORT_HTTPS=443
MYAPP_SERVICE_HOST=10.98.62.229
MYAPP_SERVICE_PORT=8080
MYAPP_PORT_8080_TCP_ADDR=10.98.62.229
SERVICE_2_PORT_80_TCP=tcp://10.98.59.151:80
SERVICE_3_PORT_80_TCP_PROTO=tcp
SERVICE_2_SERVICE_HOST=10.98.59.151
SERVICE_3_SERVICE_PORT=80
KUBERNETES_SERVICE_HOST=10.96.0.1
MYAPP_SERVICE_PORT_8080_80=8080
SERVICE_2_PORT=tcp://10.98.59.151:80
KUBERNETES_PORT=tcp://10.96.0.1:443
KUBERNETES_PORT_443_TCP_PROTO=tcp
MYAPP_PORT_8080_TCP_PORT=8080
SERVICE_2_PORT_80_TCP_PROTO=tcp
KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
SERVICE_2_PORT_80_TCP_ADDR=10.98.59.151
SERVICE_3_SERVICE_HOST=10.104.61.85
SERVICE_3_PORT=tcp://10.104.61.85:80
SERVICE_3_PORT_80_TCP_ADDR=10.104.61.85
KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
MYAPP_PORT_8080_TCP=tcp://10.98.62.229:8080
SERVICE_2_PORT_80_TCP_PORT=80
SERVICE_3_PORT_80_TCP_PORT=80
KUBERNETES_PORT_443_TCP_PORT=443
KUBERNETES_SERVICE_PORT=443
MYAPP_PORT=tcp://10.98.62.229:8080
MYAPP_PORT_8080_TCP_PROTO=tcp
NGINX_VERSION=1.20.0
NJS_VERSION=0.5.3
PKG_RELEASE=1~buster
HOME=/root

范例：volume 生成配置文件并更新生效

#configmap资源定义

[root@master1 config]# cat storage-configmap-simple-volume.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: cm-volume
data:
  author.txt: tom
  file.conf: |
    [app]
    config1
    config2
---
apiVersion: v1
kind: Pod
metadata:
  name: pod-volume-test
spec:
  volumes:
    - name: volume-config  #指定卷名
      configMap:
        name: cm-volume  #指定卷来自cm
  containers:
    - name: nginx
      image: registry.cn-beijing.aliyuncs.com/wangxiaochun/nginx:1.20.0
      volumeMounts:
      - name: volume-config #调用前面定义的卷名
        mountPath: /cmap/   #指定Pod中的挂载点目录

#应用

kubectl apply -f storage-configmap-simple-volume.yaml

#验证配置文件

root@master1 config]# kubectl exec -it pod-volume-test -- sh 
# ls /cmap 
author.txt  file.conf
# cat /cmap/author.txt
tom# cat /cmap/file.conf
[app]
config1
config2

#在线更新配置文件中的内容

kubectl edit cm cm-volume

[root@master1 config]# kubectl edit cm cm-volume 
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  author.txt: tom
  file.conf: |
    [app]
    config1
    config2
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"author.txt":"tom","file.conf":"[app]\nconfig1\nconfig2\n"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-volum
e","namespace":"default"}}
  creationTimestamp: "2026-05-24T11:33:32Z"
  name: cm-volume
  namespace: default
  resourceVersion: "329194"

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  author.txt: jack
  file.conf: |
    [app]
    config1
    config2
    config3
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"author.txt":"tom","file.conf":"[app]\nconfig1\nconfig2\n"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-volum
e","namespace":"default"}}
  creationTimestamp: "2026-05-24T11:33:32Z"
  name: cm-volume
  namespace: default
  resourceVersion: "329194"
  uid: c38717cb-0389-41c7-a306-9223505d2fef

#等一会儿进入pod可以看到配置文件变化

[root@master1 config]# kubectl exec -it pod-volume-test -- sh 
# 
#  cat /cmap/author.txt
tom# cat /cmap/file.conf
[app]
config1
config2
# cat /cmap/author.txt
tom#  cat /cmap/file.conf
[app]
config1
config2
# 
# cat /cmap/author.txt
jack# 
#  cat /cmap/file.conf
[app]
config1
config2
config3
#

#结果显示：无需重启pod对象，只要等待十几秒后，配置信息自动发生了变动

基于volume 生成配置文件支持pod配置文件动态更新

环境变量不支持

#查看一下文件的存储方式

文件不是真实文件是软链接 ..data是文件

#  ls -la /cmap
total 0
drwxrwxrwx 3 root root 94 May 24 11:39 .
drwxr-xr-x 1 root root 51 May 24 11:33 ..
drwxr-xr-x 2 root root 41 May 24 11:39 ..2026_05_24_11_39_41.690578659
lrwxrwxrwx 1 root root 31 May 24 11:39 ..data -> ..2026_05_24_11_39_41.690578659
lrwxrwxrwx 1 root root 17 May 24 11:33 author.txt -> ..data/author.txt
lrwxrwxrwx 1 root root 16 May 24 11:33 file.conf -> ..data/file.conf

也是软链接指向时间戳时间戳一变会生成新的文件指向新的配置发生变化的当前时间

# ls -la /cmap/..data 
lrwxrwxrwx 1 root root 31 May 24 11:39 /cmap/..data -> ..2026_05_24_11_39_41.690578659

再在线修改

kubectl edit cm cm-volume

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  author.txt: jack
  file.conf: |
    [app]
    config1
    config2
    config3
    config4
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"author.txt":"tom","file.conf":"[app]\nconfig1\nconfig2\n"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-volum
e","namespace":"default"}}
  creationTimestamp: "2026-05-24T11:33:32Z"
  name: cm-volume

[root@master1 config]# kubectl exec -it pod-volume-test -- sh 
# 
# ls -la /cmap/..data 
lrwxrwxrwx 1 root root 32 May 24 11:50 /cmap/..data -> ..2026_05_24_11_50_56.2938100345

# cat /cmap/file.conf
[app]
config1
config2
config3
config4

#结果显示：
#这些文件虽然看起来是在挂载的目录下，实际上，它是经过了两层的软连接才能找到真正挂载的文件
容器内挂载目录的生成的文件file --> ..data/file -->
..YYYY_MM_DD_HH_MM_SS.XXXXXXXX/file
#通过这种双层软连接的方式，只要容器支持重载技术，那么只需要更改配置文件就可以实现容器应用的变动

configmap表现磁盘文件支持动态更新 configmap文件改变了pod里面也改双重软连接最新数据放到新建带最新时间戳新目录下实现自动更新，通过时间戳机制实现

时间戳文件夹实现，k8s自动创建，把新的更改过的新数据放在新建的时间戳新目录下，并且修改原有的文件软连接，删掉旧路径时间戳，指向新的时间戳

环境变量不支持

范例：volume 挂载CM中的全部内容

#命令行创建CM,创建nginx的配置信息

mkdir nginx-conf.d

[root@master1 nginx-conf.d]# cat default.conf 
server {
    listen       8080;
    server_name  localhost;
    #access_log  /var/log/nginx/host.access.log  main;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}

[root@master1 nginx-conf.d]# cat myserver.conf
server {
    listen 8888;
    server_name www.org;
    include /etc/nginx/conf.d/myserver-*.cfg;
    location / {
        root /usr/share/nginx/html;
    }
}

[root@master1 nginx-conf.d]# cat myserver-gzip.cfg 
gzip on;
gzip_comp_level 5;
gzip_proxied     expired no-cache no-store private auth;
gzip_types text/plain text/css application/xml text/javascript;

[root@master1 nginx-conf.d]# cat myserver-status.cfg 
location /nginx-status {
    stub_status on;
    access_log off;
}

#命令行创建CM

kubectl create configmap cm-nginx-conf-files --from-file=nginx-conf.d/default.conf

[root@master1 config]# kubectl create configmap cm-nginx-conf-files --from-file=nginx-conf.d/default.conf
configmap/cm-nginx-conf-files created
[root@master1 config]# kubectl get cm
NAME                  DATA   AGE
cm-nginx-conf-files   1      4s
envoy-config          1      10d
kube-root-ca.crt      1      14d

#清单文件

[root@master1 config]# cat storage-configmap-nginx-file.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: cm-nginx-index
data:
  index.html: "Nginx Configmap page!"  #单行内容的文件生成configmap
---
apiVersion: v1
kind: Pod
metadata:
  name: pod-nginx-conf-configmap
spec:
  volumes:
  - name: nginx-conf
    configMap:
      name: cm-nginx-conf-files
      optional: false
  - name: nginx-index
    configMap:
      name: cm-nginx-index
      optional: false  
  containers:
  - image: registry.cn-beijing.aliyuncs.com/wangxiaochun/nginx:1.20.0
    name: nginx
    volumeMounts:
    - name: nginx-conf
      mountPath: /etc/nginx/conf.d/
      readOnly: true
    - name: nginx-index
      mountPath: /usr/share/nginx/html/
      readOnly: true

kubectl apply -f storage-configmap-nginx-file.yaml

[root@master1 config]# kubectl get cm 
NAME                  DATA   AGE
cm-nginx-conf-files   1      4m21s
cm-nginx-index        1      13s
envoy-config          1      10d
kube-root-ca.crt      1      14d

root@master1 config]# kubectl get pod -o wide
NAME                                        READY   STATUS    RESTARTS         AGE     IP             NODE        NOMINATED NODE   READINESS GATES
controller-deployment-demo-5f884bb8-2ppvf   1/1     Running   5 (5h13m ago)    45h     10.244.1.192   node1.org   <none>           <none>
controller-deployment-demo-5f884bb8-fscrl   1/1     Running   14 (5h13m ago)   8d      10.244.1.193   node1.org   <none>           <none>
controller-deployment-demo-5f884bb8-rfsbv   1/1     Running   13 (5h13m ago)   7d21h   10.244.1.194   node1.org   <none>           <none>
pod-nginx-conf-configmap                    1/1     Running   0                70s     10.244.2.192   node2.org   <none>           <none>

[root@master1 config]# curl 10.244.2.192:8080
Nginx Configmap page![root@master1 config]#

在线修改configmap

kubectl edit cm cm-nginx-index

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  index.html: Nginx Configmap page!
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"index.html":"Nginx Configmap page!"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-nginx-index","namespace":"d
efault"}}
  creationTimestamp: "2026-05-24T12:24:54Z"
  name: cm-nginx-index
  namespace: default
  resourceVersion: "335381"
  uid: d2d3a858-109f-4b18-9150-5b97d5b3fe69

[root@master1 config]# kubectl edit cm cm-nginx-index
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  index.html: Nginx Configmap page!2.0
kind: ConfigMap
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","data":{"index.html":"Nginx Configmap page!"},"kind":"ConfigMap","metadata":{"annotations":{},"name":"cm-nginx-index","namespace":"d
efault"}}
  creationTimestamp: "2026-05-24T12:24:54Z"
  name: cm-nginx-index
  namespace: default

网页文件更新了

[root@master1 config]# curl 10.244.2.192:8080
Nginx Configmap page!2.0[root@master1 config]#

修改配置文件

kubectl edit cm cm-nginx-conf-files

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  default.conf: |
    server {
        listen       8080;
        server_name  localhost;
        #access_log  /var/log/nginx/host.access.log  main;
        location / {
            root   /usr/share/nginx/html;
            index  index.html index.htm;
        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {

# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
data:
  default.conf: |
    server {
        listen       8888;
        server_name  localhost;
        #access_log  /var/log/nginx/host.access.log  main;
        location / {
            root   /usr/share/nginx/html;
            index  index.html index.htm;
        }
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   /usr/share/nginx/html;
        }
    }

改了配置文件

[root@master1 ~]# kubectl exec -it pod-nginx-conf-configmap -- cat /etc/nginx/conf.d/default.conf
server {
    listen       8888;
    server_name  localhost;
    #access_log  /var/log/nginx/host.access.log  main;
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}

没有生效

[root@master1 config]# curl 10.244.2.192:8888
curl: (7) Failed to connect to 10.244.2.192 port 8888: Connection refused
[root@master1 config]# curl 10.244.2.192:8080
Nginx Configmap page!2.0[root@master1 config]#

要重启可以生效

[root@master1 ~]# kubectl exec -it pod-nginx-conf-configmap -- bash
root@pod-nginx-conf-configmap:/# ng
ngettext     nginx        nginx-debug  
root@pod-nginx-conf-configmap:/# ng
ngettext     nginx        nginx-debug  
root@pod-nginx-conf-configmap:/# nginx -s reload
2026/05/24 12:36:11 [notice] 49#49: signal process started

[root@master1 config]# curl 10.244.2.192:8888             
Nginx Configmap page!2.0[root@master1 config]#

posted @ 2026-05-24 20:39 minger_lcm 阅读(18) 评论(0) 收藏举报

刷新页面返回顶部

kubernetes的配置管理configmap管理

configmap

公告