文章目录
- 计算机系统
- 5G云计算
- 第三章 LINUX Kubernetes 配置资源管理
- 一、Secret
- 1.Secret 四种类型
- 1）kubernetes.io/service-account-token
- 2）Opaque
- 3）kubernetes.io/dockerconfigjson
- 4）kubernetes.io/tls
- 2.Pod 需要先引用才能使用某个 secret，Pod 有 3 种方式来使用 secret
- 二.ConfigMap
计算机系统
5G云计算
第三章 LINUX Kubernetes 配置资源管理
一、Secret
Secret 是用来保存密码、token、密钥等敏感数据的 k8s 资源，这类数据虽然也可以存放在 Pod 或者镜像中，但是放在 Secret 中是为了更方便的控制如何使用数据，并减少暴露的风险
1.Secret 四种类型
1）kubernetes.io/service-account-token
由 Kubernetes 自动创建，用来访问 APIServer 的 Secret，Pod 会默认使用这个 Secret 与 APIServer 通信， 并且会自动挂载到 Pod 的 /run/secrets/kubernetes.io/serviceaccount 目录中
2）Opaque
base64 编码格式的 Secret，用来存储用户自定义的密码、密钥等，默认的 Secret 类型
3）kubernetes.io/dockerconfigjson
用来存储私有 docker registry 的认证信息
4）kubernetes.io/tls
用来存储 TLS 证书和私钥信息
2.Pod 需要先引用才能使用某个 secret，Pod 有 3 种方式来使用 secret
1）作为挂载到一个或多个容器上的卷 中的文件
2）作为容器的环境变量
3）由 kubelet 在为 Pod 拉取镜像时使用
应用场景：凭据
https://kubernetes.io/docs/concepts/configuration/secret/
//创建 Secret
1、用kubectl create secret命令创建Secret
echo -n 'zhangsan' > username.txt
echo -n 'abc1234' > password.txt
kubectl create secret generic mysecret --from-file=username.txt --from-file=password.txt
kubectl get secrets
NAME TYPE DATA AGE
default-token-sggl5 kubernetes.io/service-account-token 3 6d21h
mysecret Opaque 2 3s
nfs-client-provisioner-token-xpkn5 kubernetes.io/service-account-token 3 3d2h
kubectl describe secret mysecret
Name: mysecret
Namespace: default
Labels: <none>
Annotations: <none>
Type: Opaque
Data
====
username.txt: 8 bytes
password.txt: 7 bytes
//get或describe指令都不会展示secret的实际内容，这是出于对数据的保护的考虑
2、内容用 base64 编码，创建Secret
echo -n zhangsan | base64
emhhbmdzYW4K=
echo -n abc1234 | base64
YWJjMTIzNAo==
kubectl create secret generic mysecret1 --from-literal=myname=lisi
kubectl get secrets
NAME TYPE DATA AGE
default-token-sggl5 kubernetes.io/service-account-token 3 6d21h
mysecret Opaque 2 6m
mysecret1 Opaque 1 12s
nfs-client-provisioner-token-xpkn5 kubernetes.io/service-account-token 3 3d2h
kubectl get secret mysecret1 -o yaml
apiVersion: v1
data:
myname: bGlzaQ==
kind: Secret
metadata:
creationTimestamp: "2023-08-17T09:04:08Z"
managedFields:
- apiVersion: v1
fieldsType: FieldsV1
fieldsV1:
f:data:
.: {}
f:myname: {}
f:type: {}
manager: kubectl-create
operation: Update
time: "2023-08-17T09:04:08Z"
name: mysecret1
namespace: default
resourceVersion: "160205"
selfLink: /api/v1/namespaces/default/secrets/mysecret1
uid: 53c6b51e-4089-456a-8ee7-9aefba21db40
type: Opaque
//使用方式
1、将 Secret 挂载到 Volume 中，以 Volume 的形式挂载到 Pod 的某个目录下
vim secret-test.yaml
apiVersion: v1
kind: Pod
metadata:
name: mypod
spec:
containers:
- name: nginx
image: nginx
volumeMounts:
- name: secrets
mountPath: "/etc/secrets"
readOnly: true
volumes:
- name: secrets
secret:
secretName: mysecret
kubectl create -f secret-test.yaml
kubectl get pods
NAME READY STATUS RESTARTS AGE
mypod 1/1 Running 0 46s
nfs-client-provisioner-55bbbfbb9f-bwrhm 1/1 Running 0 2d1h
kubectl exec -it mypod bash
# cd /etc/secrets/
# ls
password.txt username.txt
# cat username.txt
zhangsan#
2、将 Secret 导出到环境变量中
vim secret-test1.yaml
apiVersion: v1
kind: Pod
metadata:
name: mypod1
spec:
containers:
- name: nginx
image: nginx
env:
- name: TEST_USER
valueFrom:
secretKeyRef:
name: mysecret
key: username.txt
- name: TEST_PASSWORD
valueFrom:
secretKeyRef:
name: mysecret
key: password.txt
envFrom:
- secretRef:
name: mysecret1
kubectl apply -f secret-test1.yaml
kubectl get pods
NAME READY STATUS RESTARTS AGE
NAME READY STATUS RESTARTS AGE
mypod 1/1 Running 0 3m9s
mypod1 1/1 Running 0 30s
nfs-client-provisioner-55bbbfbb9f-bwrhm 1/1 Running 0 2d1h
kubectl exec -it mypod1 bash
# echo $TEST_USER
zhangsan
# echo $TEST_PASSWORD
abc1234
二.ConfigMap
与Secret类似，区别在于ConfigMap保存的是不需要加密配置的信息
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
应用场景：应用配置
//创建 ConfigMap
1、使用目录创建
mkdir /opt/configmap/
vim /opt/configmap/game.config
enemy.types=aliens,monsters
player.maximum-lives=5
vim /opt/configmap/ui.config
color.good=purple
color.bad=yellow
allow.textmode=true
ls /opt/configmap/
game.config
ui.config
kubectl create configmap game-config --from-file=/opt/configmap/
//--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
kubectl get cm
NAME DATA AGE
game-config 2 3s
kube-root-ca.crt 1 6d21h
kubectl get cm game-config -o yaml
apiVersion: v1
data:
game.config: "enemy.types=aliens,monsters\nplayer.maximum-lives=5 \n"
ui.config: |
color.good=purple
color.bad=yellow
allow.textmode=true
kind: ConfigMap
metadata:
creationTimestamp: "2023-08-17T09:13:28Z"
managedFields:
- apiVersion: v1
fieldsType: FieldsV1
fieldsV1:
f:data:
.: {}
f:game.config: {}
f:ui.config: {}
manager: kubectl-create
operation: Update
time: "2023-08-17T09:13:28Z"
name: game-config
namespace: default
resourceVersion: "161245"
selfLink: /api/v1/namespaces/default/configmaps/game-config
uid: b198ecb4-2d62-4d5e-bbd8-3fe609986ec4
2、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
--from-file 这个参数可以使用多次，即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
kubectl create configmap game-config-2 --from-file=/opt/configmap/game.config --from-file=/opt/configmap/ui.config
kubectl get configmaps game-config-2 -o yaml
kubectl describe cm game-config-2
3、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=good
kubectl get configmaps special-config -o yaml
apiVersion: v1
data:
special.how: very
special.type: good
kind: ConfigMap
metadata:
creationTimestamp: "2023-08-17T09:16:42Z"
managedFields:
- apiVersion: v1
fieldsType: FieldsV1
fieldsV1:
f:data:
.: {}
f:special.how: {}
f:special.type: {}
manager: kubectl-create
operation: Update
time: "2023-08-17T09:16:42Z"
name: special-config
namespace: default
resourceVersion: "161613"
selfLink: /api/v1/namespaces/default/configmaps/special-config
uid: be38184f-ac39-4e38-92df-87e01a2b7a60
kubectl delete cm --all
kubectl delete pod --all
//Pod 中使用 ConfigMap
1、使用 ConfigMap 来替代环境变量
vim env.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: special-config
namespace: default
data:
special.how: very
special.type: good
---
apiVersion: v1
kind: ConfigMap
metadata:
name: env-config
namespace: default
data:
log_level: INFO
kubectl apply -f env.yaml
kubectl get cm
NAME DATA AGE
env-config 1 3s
kube-root-ca.crt 1 57s
special-config 2 3s
//Pod的创建
vim test-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: test-pod
spec:
containers:
- name: busybox
image: busybox:1.28.4
command: [ "/bin/sh", "-c", "env" ]
env:
- name: SPECIAL_HOW_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
kubectl apply -f test-pod.yaml
kubectl get pods
NAME READY STATUS RESTARTS AGE
nfs-client-provisioner-55bbbfbb9f-s2fcr 1/1 Running 0 2m8s
test-pod 0/1 Completed 0 20s
kubectl logs test-pod
KUBERNETES_SERVICE_PORT=443
KUBERNETES_PORT=tcp://10.0.0.1:443
HOSTNAME=test-pod
SHLVL=1
SPECIAL_HOW_KEY=very #赋值变量 SPECIAL_HOW_KEY 的值为 special-config 的 special.how: very
HOME=/root
SPECIAL_TYPE_KEY=good
KUBERNETES_PORT_443_TCP_ADDR=10.0.0.1
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
KUBERNETES_PORT_443_TCP_PORT=443
KUBERNETES_PORT_443_TCP_PROTO=tcp
log_level=INFO #引入 env-config 的变量 log_level: INFO
KUBERNETES_SERVICE_PORT_HTTPS=443
KUBERNETES_PORT_443_TCP=tcp://10.0.0.1:443
KUBERNETES_SERVICE_HOST=10.0.0.1
PWD=/
2、用 ConfigMap 设置命令行参数
vim test-pod2.yaml
apiVersion: v1
kind: Pod
metadata:
name: test-pod2
spec:
containers:
- name: busybox
image: busybox:1.28.4
command:
- /bin/sh
- -c
- echo "$(SPECIAL_HOW_KEY) $(SPECIAL_TYPE_KEY)"
env:
- name: SPECIAL_HOW_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
kubectl apply -f test-pod2.yaml
kubectl get pods
NAME READY STATUS RESTARTS AGE
nfs-client-provisioner-55bbbfbb9f-s2fcr 1/1 Running 0 4m10s
test-pod 0/1 Completed 0 2m22s
test-pod2 0/1 Completed 0 7s
kubectl logs test-pod2
very good
3、通过数据卷插件使用ConfigMap
在数据卷里面使用 ConfigMap，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
vim test-pod3.yaml
apiVersion: v1
kind: Pod
metadata:
name: test-pod3
spec:
containers:
- name: busybox
image: busybox:1.28.4
command: [ "/bin/sh", "-c", "sleep 36000" ]
volumeMounts:
- name: config-volume
mountPath: /etc/config
volumes:
- name: config-volume
configMap:
name: special-config
restartPolicy: Never
kubectl apply -f test-pod3.yaml
kubectl get pods
NAME READY STATUS RESTARTS AGE
nfs-client-provisioner-55bbbfbb9f-s2fcr 1/1 Running 0 5m20s
test-pod 0/1 Completed 0 3m32s
test-pod2 0/1 Completed 0 77s
test-pod3 1/1 Running 0 6s
kubectl exec -it test-pod3 sh
# cd /etc/config/
# ls
special.how special.type
# vi special.how
# vi special.type
RESTARTS AGE
nfs-client-provisioner-55bbbfbb9f-s2fcr 1/1 Running 0 5m20s
test-pod 0/1 Completed 0 3m32s
test-pod2 0/1 Completed 0 77s
test-pod3 1/1 Running 0 6s
kubectl exec -it test-pod3 sh
# cd /etc/config/
# ls
special.how special.type
# vi special.how
# vi special.type
