k8s踩坑记录——证书一年有效期

kubernetes集群证书重签

依照https://github.com/strongit/kubeadm-ha/ 安装步骤，kubeadm init安装后的集群存在证书过期问题。现修复如下：

思路如下，

1、保留ca.crt ca.key front-proxy-ca.crt front-proxy-ca.key，根证书有效期十年

2、openssl重新签注

3、kubeadm alpha phase 生成config

[root@k8s-master01 pki]# cat csr.conf
[ req ]
default_bits = 2048
prompt = no
default_md = sha256
req_extensions = req_ext
distinguished_name = dn

[ dn ]
C = CN
ST = BeiJing
L = BeiJing
O = k8s
OU = System
CN = kubernetes

[ req_ext ]
subjectAltName = @alt_names

[ alt_names ]
DNS.1 = kubernetes
DNS.2 = kubernetes.default
DNS.3 = kubernetes.default.svc
DNS.4 = kubernetes.default.svc.cluster
DNS.5 = kubernetes.default.svc.cluster.local
DNS.6 = k8s-master01
DNS.7 = k8s-master02
DNS.8 = k8s-master03
IP.1 = IP
IP.2 = IP

[ v3_ext ]
authorityKeyIdentifier=keyid,issuer:always
basicConstraints=CA:FALSE
keyUsage=digitalSignature,nonRepudiation,keyEncipherment,dataEncipherment
extendedKeyUsage=serverAuth,clientAuth
subjectAltName=@alt_names

 openssl genrsa -out apiserver.key 2048 
 openssl req -new -key apiserver.key -out apiserver.csr -config csr.conf
 openssl x509 -req -in apiserver.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out apiserver.crt -days 10000 -extensions v3_ext -extfile csr.conf
 openssl x509  -noout -text -in ./apiserver.crt  |grep "Not"

 openssl genrsa -out apiserver-kubelet-client.key 2048
 openssl req -new -key apiserver-kubelet-client.key -out apiserver-kubelet-client.csr -config csr.conf
 openssl x509 -req -in apiserver-kubelet-client.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out apiserver-kubelet-client.crt -days 10000 -extensions v3_ext -extfile csr.conf
 openssl x509  -noout -text -in ./apiserver-kubelet-client.crt  |grep "Not"

 openssl genrsa -out front-proxy-client.key 2048
 openssl req -new -key front-proxy-client.key -out front-proxy-client.csr -config csr.conf
 openssl x509 -req -in front-proxy-client.csr -CA front-proxy-ca.crt -CAkey front-proxy-ca.key -CAcreateserial -out front-proxy-client.crt -days 10000 -extensions v3_ext -extfile csr.conf
 openssl x509  -noout -text -in ./front-proxy-client.crt  |grep "Not"

kubeadm alpha phase certs all --config kubeadm-config.yaml

kubeadm alpha phase kubelet config write-to-disk --config kubeadm-config.yaml
kubeadm alpha phase kubelet write-env-file --config kubeadm-config.yaml
kubeadm alpha phase kubeconfig kubelet --config kubeadm-config.yaml

kubeadm alpha phase kubeconfig all --config kubeadm-config.yaml

kubeadm alpha phase controlplane all --config kubeadm-config.yaml

systemctl restart kubelet
kubeadm alpha phase mark-master --config kubeadm-config.yaml
cp /etc/kubernetes/admin.conf ~/.kube/config

重启集群后，执行kubelet logs pods XXXX -n kube-system报错如下：Error from server (Forbidden): Forbidden (user=kubernetes, verb=get, resource=nodes, subresource=proxy) ( pods/log kube-scheduler-k8s-master01)

解决方案：kubectl create clusterrolebinding system:kubernetes --clusterrole=cluster-admin --user=system:kubernetes

ingress的tls设置

对ingress中的域名进行tls安全证书的设置步骤如下：

创建自签名的秘钥与ssl证书；

将证书保存到kubernetes集群的1个Secret资源对象上；

设置Secret资源对象到ingress中。

根据网站域名是1个还是多个，前两步的操作稍有不同，第3步操作相同，下面以多域名的操作为例：

1. 生成ca证书

   [root@kubenode1 ~]# mkdir -p /etc/kubernetes/ingress

   [root@kubenode1 ~]# cd /etc/kubernetes/ingress/

   [root@kubenode1 ingress]# openssl genrsa -out ca.key 2048

   [root@kubenode1 ingress]# openssl req -x509 -new -nodes -key ca.key -days 3560 -out ca.crt -subj "/CN=ingress-ca"

2. 修改openssl.cnf文件
   #对于多域名，生成ssl证书需要使用额外的x509v3配置文件辅助；
   #在[alt_names]字段中设置多域名
   [root@kubenode1 ingress]# cp /etc/pki/tls/openssl.cnf .
   [root@kubenode1 ingress]# vim openssl.cnf

[ req ]

#第126行，取消注释

req_extensions = v3_req # The extensions to add to a certificate request

[ v3_req ]

#Extensions to add to a certificate request

basicConstraints = CA:FALSE

keyUsage = nonRepudiation, digitalSignature, keyEncipherment

#第224行之后，新增部分

subjectAltName = @alt_names

[alt_names]

DNS.1 = nginx01-svc-tls.me

DNS.2 = nginx02-svc-tls.me

3. 生成ingress ssl证书

#基于修改的openssl.cnf与ca证书生成ingress ssl证书

#生成秘钥

[root@kubenode1 ingress]# openssl genrsa -out ingress.key 2048

#生成csr文件

[root@kubenode1 ingress]# openssl req -new -key ingress.key -out ingress.csr -subj "/CN=nginx-svc-tls" -config openssl.cnf

#生成证书

[root@kubenode1 ingress]# openssl x509 -req -in ingress.csr -CA ca.crt -CAkey ca.key -CAcreateserial -out ingress.crt -days 3650 -extensions v3_req -extfile openssl.cnf

4. 生成Secret资源对象

   Secret对象的主要作用是保管私密数据，如：密码，OAuth Tokens，ssh Keys等信息。将私密信息存放在Secret对象中，比直接放在Pod或者Docker image中更安全，更便于使用与分发。

Secret对象创建完成之后，可通过3种方式调用：

在创建Pod时，通过为Pod指定Service Account来自动使用；

通过挂载Secret到Pod来使用；

Docker image下载时使用，通过指定Pod的spc.ImagePullSecrets来引用。

#编辑secret-ingress.yaml文件，将ingress.key与ingress.crt的内容复制到yaml文件中；

#注意1：Secret的”data”域的各子域的值必须为BASE64编码；

#注意2：复制key与crt的内容时去掉换行符，变成一行

[root@kubenode1 ingress]# cd /usr/local/src/yaml/ingress/

[root@kubenode1 ingress]# touch secret-ingress.yaml

[root@kubenode1 ingress]# vim secret-ingress.yaml

apiVersion: v1

kind: Secret

metadata:

name: secret-ingress

#1.8.x之后使用kubernetes.io/tls替换Opaque

type: kubernetes.io/tls

data:

tls.crt: 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

tls.key: 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

#生成Secret资源对象

[root@kubenode1 ingress]# kubectl create -f secret-ingress.yaml

#以上编辑yaml文件，使用”kubectl create”命令生成Secret对象在步骤上更清晰；

#但可以利用”kubectl create secret tls”命令直接创建Secret对象

[root@kubenode1 ingress]# kubectl create secret tls secret-ingress --key /etc/kubernetes/ingress/ingress.key --cert /etc/kubernetes/ingress/ingress.crt

5. 创建后端服务

   #编辑后端服务nginx01-svc-tls.yaml

   [root@kubenode1 ingress]# touch nginx01-svc-tls.yaml

   [root@kubenode1 ingress]# vim nginx01-svc-tls.yaml

   apiVersion: extensions/v1beta1

   kind: Deployment

   metadata:

   name: nginx01-tls

   spec:

   replicas: 1

   template:

   metadata:

   labels:

   name: nginx01-tls

   spec:

   containers:

   • name: nginx01-tls

     image: nginx:latest

     ports:

     • containerPort: 80

       apiVersion: v1

       kind: Service

       metadata:

       name: nginx01-svc-tls

       spec:

       ports:

       #Service服务监听的端口号

     • port: 443
       #后端提供真实服务的Pod提供的端口号
       targetPort: 80
       name: https
       selector:
       name: nginx01-tls

#编辑后端服务nginx02-svc-tls.yaml

[root@kubenode1 ingress]# cp nginx01-svc-tls.yaml nginx02-svc-tls.yaml

[root@kubenode1 ingress]# sed -i 's|nginx01|nginx02|g' nginx02-svc-tls.yaml

#生成后端服务

[root@kubenode1 ingress]# kubectl create -f nginx01-svc-tls.yaml

[root@kubenode1 ingress]# kubectl create -f nginx02-svc-tls.yaml

#修改提供后端服务的nginx容器的html文件；

#通过”kubectl exec -ti <pod-name> -c <container-name> /bin/bash”进入容器修改；pod-name可通过命令”kubectl get pods -o wide”获取；container-name即yaml文件中定义的名字

[root@kubenode1 ingress]# kubectl get pods -o wide

#nginx官方容器的index.html文件在/usr/share/nginx/html/目录下

[root@kubenode1 ingress]# kubectl exec -ti nginx01-tls-59fbf6696c-qfq4k -c nginx01-tls /bin/bash

root@nginx01-tls-59fbf6696c-qfq4k:/# echo "<h1>Welcome to test site nginx01-svc-tls</h1>" > /usr/share/nginx/html/index.html

root@nginx01-tls-59fbf6696c-qfq4k:/# cat /usr/share/nginx/html/index.html

root@nginx01-tls-59fbf6696c-qfq4k:/# exit

[root@kubenode1 ingress]# kubectl exec -ti nginx02-tls-5559fd9bc7-dfbrp -c nginx02-tls /bin/bash

root@nginx02-tls-5559fd9bc7-dfbrp:/# echo "<h1>Welcome to test site nginx02-svc-tls</h1>" > /usr/share/nginx/html/index.html

root@nginx02-tls-5559fd9bc7-dfbrp:/# cat /usr/share/nginx/html/index.html

root@nginx02-tls-5559fd9bc7-dfbrp:/# exit

6. 创建ingress对象

   复制代码

   #编辑ingress对象yaml文件；

   #在”spec”域下新增“tls”子域，”hosts”字段加入多域名，“secretName”字段调用对应的Secret资源；

   #1个ingress对象只能使用1个Secret对象（“secretName”字段value唯一），即只能使用1个证书，该正式需要支持”hosts”字段下所有域名；

   #“secretName”字段一定要置于域名列表最后的位置；

   #”hosts”字段的域名需要匹配”rules”字段域名；

   #ingress默认情况下，当不配置证书或者证书配置错误时，会默认给出一个tls证书；如“secretName”字段配置了2个值，则所有域名采用默认证书；如”hosts”字段少配置一个域名，缺失的域名会采用默认证书；

   #更新ingress证书可能需要等待一段时间才能生效

   [root@kubenode1 ingress]# touch nginx-svc-tls-ingress.yaml

   [root@kubenode1 ingress]# vim nginx-svc-tls-ingress.yaml

   apiVersion: extensions/v1beta1

   kind: Ingress

   metadata:

   name: ingress-tls

   spec:

   tls:

   • hosts:
   • nginx01-svc-tls.me
   • nginx02-svc-tls.me
     secretName: secret-ingress
     rules:
   • host: nginx01-svc-tls.me
     http:
     paths:

     • backend:

       serviceName: nginx01-svc-tls

       #后端服务监听端口，区别于提供真实服务的容器监听端口

       servicePort: 443

   • host: nginx02-svc-tls.me
     http:
     paths:

     • backend:

       serviceName: nginx02-svc-tls

       servicePort: 443

#生成ingress对象

[root@kubenode1 ingress]# kubectl create -f nginx-svc-tls-ingress.yaml

[root@kubenode1 ingress]# kubectl get ingress

7. 验证

   #采用--resolve参数模拟dns解析，目标地址为域名；

   #http访问时被重定向，采用https访问正常

   [root@kubenode1 ingress]# curl --resolve nginx01-svc-tls.me:80:172.30.200.21 http://nginx01-svc-tls.me

   [root@kubenode1 ingress]# curl --resolve nginx01-svc-tls.me:443:172.30.200.21 -k https://nginx01-svc-tls.me

#或者采用-H参数设置http头中需要访问的域名，目标地址为ip地址

[root@kubenode1 ingress]# curl -H 'Host:nginx01-svc-tls.me' -k https://172.30.200.23

[root@kubenode1 ingress]# curl -H 'Host:nginx02-svc-tls.me' -k https://172.30.200.23

在本地浏览器访问host主机（注意提前绑定域名）： http://nginx01-svc-tls.me

采用http访问，重定向自动跳转为https访问