Adrian Goins 最近举办了关于如何使用 K3s 和 Traefik 保护和控制边缘的 Kubernetes 大师班，演示了如何访问 K3s 的 Traefik Proxy 仪表板，可以通过以下途径注册观看回放：https://more.suse.com/MC_Secure_Edge_K3s_Traefik.html
Rancher Desktop 创建了一个单节点 K3s 集群，我非常好奇在使用 Rancher Desktop 时，是否可以访问 Traefik Proxy 仪表板。我在 Adrian 的课程上提出了这个问题，他说应该可以，于是我便开始着手操作。
注意：本文使用的环境为 Linux 操作系统，如 Mac 或 Windows 需视情况调整参数。
本文参考了 Adrian 在 GitHub 上发布的一些课程: https://github.com/traefik-workshops/k3s-and-traefik-proxy
首先，克隆 Adrian 的 repo：
> git clone https://github.com/traefik-workshops/k3s-and-traefik-proxy.git
> cd k3s-and-traefik-proxy/
第一课: 暴露 Traefik 仪表盘
注意：01-Expose-the-Dashboard 中的所有文件目前都没有在 Adrian 的课程中使用。
将集群 IP 设置为变量
Adrian 建议检查 kubeconfig 文件中的集群 IP 地址，Rancher Desktop 会在主机上创建一个 ~/.kube/config 文件：
> grep server ~/.kube/config
server: https://127.0.0.1:6443
> export CLUSTERIP=127.0.0.1
此时，Adrian 继续他的课程，但目前 Linux 上的 Rancher Desktop 存在一个问题：特权端口（低于 1024 的端口）无法访问。请参考 https://github.com/rancher-sandbox/rancher-desktop/issues/576
相反，Linux 上的 Rancher Desktop 用户必须了解 HTTP (80) 和 HTTPS (443) 端口已转发到哪些 Ingress 端口：
> kubectl get service -n kube-system traefik
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
traefik LoadBalancer 10.43.146.37 192.168.5.15 80:30876/TCP,443:30614/TCP 26
我们将 Ingress 端口保存到变量中，以便可以在整个课程中使用：
> export CLUSTERHTTP=`kubectl get service -n kube-system traefik -o json | jq '.spec.ports[0].nodePort'`
> export CLUSTERHTTPS=`kubectl get service -n kube-system traefik -o json | jq '.spec.ports[1].nodePort'`
切换当前 Namespace 为 kube-system
> kubectl config set-context --current --namespace kube-system
Context "rancher-desktop" modified.
创建 Service
> kubectl expose deploy/traefik -n kube-system --port=9000 --target-port=9000 --name=traefik-dashboard
service/traefik-dashboard exposed
创建 Ingress
> kubectl create ingress traefik-dashboard --rule="dashboard.traefik.$CLUSTERIP.sslip.io/*=traefik-dashboard:9000"
ingress.networking.k8s.io/traefik-dashboard created
访问仪表板
与 Adrian 步骤不同的是，我们需要在 URL 中包含 HTTP 的 Ingress 端口：
> curl -si http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/dashboard/ | head -n 1
HTTP/1.1 200 OK
> echo http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/dashboard/
http://dashboard.traefik.127.0.0.1.sslip.io:30876/dashboard/
添加 Annotations
> kubectl annotate ingress traefik-dashboard traefik.ingress.kubernetes.io/router.entrypoints=web
ingress.networking.k8s.io/traefik-dashboard annotated
第 2 课：使用 Middleware 保护仪表板
> cd 02-Secure-the-Dashboard-With-Middleware
创建用户文件
注意 Adrian 已根据研讨会提供了用户文件设置：
> cat users
user@example.com:$apr1$nWlieTS.$pbESld2QB5uYuUTAfFICr.
admin@example.com:$apr1$XMtXkoUy$IwIKiM./ujfaYf6/MsCaf1
从用户文件中创建仪表板 dashboard-users Secret
> kubectl create secret generic dashboard-users --from-file=users
secret/dashboard-users created
从 middleware-auth.yaml 创建 Middleware
> cat middleware-auth.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: dashboard-auth
spec:
basicAuth:
secret: dashboard-users
> kubectl apply -f middleware-auth.yaml
middleware.traefik.containo.us/dashboard-auth created
将 Middleware 应用到 Ingress
> kubectl annotate ingress traefik-dashboard \
traefik.ingress.kubernetes.io/router.middlewares=kube-system-dashboard-auth@kubernetescrd
ingress.networking.k8s.io/traefik-dashboard annotated
请注意，如果你在浏览器中一直访问仪表板，那么现在应该提示你输入用户名和密码：
测试 Middleware
> curl -si http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/dashboard/ | head -n 1
HTTP/1.1 401 Unauthorized
> curl -si -u 'admin@example.com:admin1234' http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/dashboard/ | head -n 1
HTTP/1.1 200 OK
创建 Middleware 以添加 /dashboard 前缀
> cat middleware-rewrite.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: dashboard-rewrite
spec:
addPrefix:
prefix: /dashboard
> kubectl apply -f middleware-rewrite.yaml
middleware.traefik.containo.us/dashboard-rewrite created
将第二个 Middleware 应用到 Ingress
> kubectl annotate ingress traefik-dashboard \
traefik.ingress.kubernetes.io/router.middlewares=kube-system-dashboard-rewrite@kubernetescrd,kube-system-dashboard-auth@kubernetescrd \
--overwrite=true
ingress.networking.k8s.io/traefik-dashboard annotated
访问没有 /dashboard/ 的仪表板
> curl -si http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/ | head -n 1
HTTP/1.1 401 Unauthorized
修复仪表板
> kubectl create ingress traefik-dashboard-api --rule="dashboard.traefik.$CLUSTERIP.sslip.io/api/*=traefik-dashboard:9000"
ingress.networking.k8s.io/traefik-dashboard-api created
> kubectl annotate ingress traefik-dashboard-api \
traefik.ingress.kubernetes.io/router.middlewares=kube-system-dashboard-auth@kubernetescrd
ingress.networking.k8s.io/traefik-dashboard-api annotated
第 3 课：使用 IngressRoute 自定义资源
> cd ../03-Use-the-IngressRoute-Custom-Resource/
将 Ingress 更改为 IngressRoutes
移除之前创建的 Ingress：
> kubectl delete ingress/traefik-dashboard ingress/traefik-dashboard-api
ingress.networking.k8s.io "traefik-dashboard" deleted
ingress.networking.k8s.io "traefik-dashboard-api" deleted
创建新的 IngressRoute，我们需要更改 IP 地址：
> cat ingressroute.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-secure
spec:
entryPoints:
- web
routes:
- kind: Rule
match: Host("dashboard.traefik.10.68.0.70.sslip.io")
services:
- name: traefik-dashboard
port: 9000
middlewares:
- name: dashboard-auth
- name: dashboard-rewrite
- kind: Rule
match: Host("dashboard.traefik.10.68.0.70.sslip.io") && PathPrefix("/api")
services:
- name: traefik-dashboard
port: 9000
middlewares:
- name: dashboard-auth
> sed -i "s/10\.68\.0\.70/${CLUSTERIP}/" ingressroute.yaml
> cat ingressroute.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-secure
spec:
entryPoints:
- web
routes:
- kind: Rule
match: Host("dashboard.traefik.127.0.0.1.sslip.io")
services:
- name: traefik-dashboard
port: 9000
middlewares:
- name: dashboard-auth
- name: dashboard-rewrite
- kind: Rule
match: Host("dashboard.traefik.127.0.0.1.sslip.io") && PathPrefix("/api")
services:
- name: traefik-dashboard
port: 9000
middlewares:
- name: dashboard-auth
> kubectl apply -f ingressroute.yaml
ingressroute.traefik.containo.us/traefik-dashboard-secure created
查看 IngressRoute
> kubectl get ingressroute traefik-dashboard -o yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
annotations:
helm.sh/hook: post-install,post-upgrade
creationTimestamp: "2022-02-11T16:01:09Z"
generation: 1
labels:
app.kubernetes.io/instance: traefik
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/name: traefik
helm.sh/chart: traefik-10.9.100
name: traefik-dashboard
namespace: kube-system
resourceVersion: "657"
uid: 7993457e-7cde-478b-82c9-76acc5eebbd9
spec:
entryPoints:
- traefik
routes:
- kind: Rule
match: PathPrefix(`/dashboard`) || PathPrefix(`/api`)
services:
- kind: TraefikService
name: api@internal
什么是 TraefikService？
> kubectl patch ingressroute/traefik-dashboard-secure --type=json --patch-file patch-dashboard-service.yaml
ingressroute.traefik.containo.us/traefik-dashboard-secure patched
> kubectl delete service traefik-dashboard
service "traefik-dashboard" deleted
> curl -si -u 'admin@example.com:admin1234' http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/ | head -n 1
HTTP/1.1 200 OK
第 4 课：使用 TLS 保护仪表板
> cd ../04-Secure-the-Dashboard-With-TLS/
设置 cert-manager
我使用了最新版本的 cert-manager，目前是 1.7.1：
> kubectl apply -f https://github.com/jetstack/cert-manager/releases/download/v1.7.1/cert-manager.yaml
customresourcedefinition.apiextensions.k8s.io/certificaterequests.cert-manager.io created
customresourcedefinition.apiextensions.k8s.io/certificates.cert-manager.io created
...
...
...
mutatingwebhookconfiguration.admissionregistration.k8s.io/cert-manager-webhook created
validatingwebhookconfiguration.admissionregistration.k8s.io/cert-manager-webhook created
> kubectl get pods -n cert-manager
NAME READY STATUS RESTARTS AGE
cert-manager-cainjector-d6cbc4d9-j8q8x 1/1 Running 0 70s
cert-manager-6d8d6b5dbb-ts2mq 1/1 Running 0 70s
cert-manager-webhook-85fb68c79b-ql658 1/1 Running 0 70s
创建 ClusterIssuer
> cat clusterissuer.yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
name: selfsigned
spec:
selfSigned: {}
> kubectl apply -f clusterissuer.yaml
clusterissuer.cert-manager.io/selfsigned created
为仪表板生成证书
我们需要更改 IP 地址：
> cat certificate.yaml
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: dashboard
spec:
subject:
organizations:
- Traefik Academy
commonName: dashboard.traefik.10.68.0.70.sslip.io
issuerRef:
kind: ClusterIssuer
name: selfsigned
secretName: dashboard-crt
> sed -i "s/10\.68\.0\.70/${CLUSTERIP}/" certificate.yaml
> cat certificate.yaml
apiVersion: cert-manager.io/v1
kind: Certificate
metadata:
name: dashboard
spec:
subject:
organizations:
- Traefik Academy
commonName: dashboard.traefik.127.0.0.1.sslip.io
issuerRef:
kind: ClusterIssuer
name: selfsigned
secretName: dashboard-crt
> kubectl apply -f certificate.yaml
certificate.cert-manager.io/dashboard created
> kubectl get secret | grep tls
k3s-serving kubernetes.io/tls 2 87m
dashboard-crt
将证书添加到 IngressRoute
> cat patch-dashboard-tls.yaml
- op: replace
path: /spec/entryPoints
value:
- websecure
- op: add
path: /spec/tls
value:
secretName: dashboard-crt
> kubectl patch ingressroute/traefik-dashboard-secure \
--type=json \
--patch-file patch-dashboard-tls.yaml
ingressroute.traefik.containo.us/traefik-dashboard-secure patched
> echo https://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTPS/
https://dashboard.traefik.127.0.0.1.sslip.io:30614/
添加 HTTP 重定向
> cat middleware-scheme.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: redirect-permanent
spec:
redirectScheme:
permanent: true
scheme: https
需要在 middleware-scheme.yaml 添加 HTTPS 端口，并在 ingressroute.yaml 中更改 IP 地址：
> echo " port: \"${CLUSTERHTTPS}\"" >> middleware-scheme.yaml
> cat middleware-scheme.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: redirect-permanent
spec:
redirectScheme:
permanent: true
scheme: https
port: "30614"
> kubectl apply -f middleware-scheme.yaml
middleware.traefik.containo.us/redirect-permanent created
> cat ingressroute.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-http
spec:
entryPoints:
- web
routes:
- kind: Rule
match: Host("dashboard.traefik.10.68.0.70.sslip.io")
services:
- name: api@internal
kind: TraefikService
middlewares:
- name: redirect-permanent
> sed -i "s/10\.68\.0\.70/${CLUSTERIP}/" ingressroute.yaml
> cat ingressroute.yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-http
spec:
entryPoints:
- web
routes:
- kind: Rule
match: Host("dashboard.traefik.127.0.0.1.sslip.io")
services:
- name: api@internal
kind: TraefikService
middlewares:
- name: redirect-permanent
> kubectl apply -f ingressroute.yaml
ingressroute.traefik.containo.us/traefik-dashboard-http created
> curl -si http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/ | head -n 1
HTTP/1.1 301 Moved Permanently
如果我们删除 head 命令，我们可以看到它被移动到了哪里：
> curl -si http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/
HTTP/1.1 301 Moved Permanently
Location: https://dashboard.traefik.127.0.0.1.sslip.io:30614/
Date: Fri, 11 Feb 2022 17:40:15 GMT
Content-Length: 17
Content-Type: text/plain; charset=utf-8
该位置应包括 HTTPS 的 Ingress 端口：
> echo http://dashboard.traefik.$CLUSTERIP.sslip.io:$CLUSTERHTTP/
http://dashboard.traefik.127.0.0.1.sslip.io:30876/
如果我们在 Web 浏览器中打开 URL，它应该重定向到 HTTPS 站点。如果没有，你可能需要清除 Web 浏览器的缓存。