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1. 题目

Using Kubernetes context cluster-2 
Create and configure Istio resources necessary for routing all traffic destined 
for http://example.org through the default Istio egress gateway running in the 
istio-system namespace. Ensure the following:

Use istio=egressgateway as the gateway selector.
Use ServiceEntry for the host example.org and HTTP protocol.
The gateway resource must be named exampleorg-egress.
Use fully qualified hostnames when referencing.
All resources must be created in the egress namespace.

2. 解题

2.1 获取模板

这题一共需要4段配置.

1. serviceEntry
2. gateway
3. dr
4. vs
   
   
   获取第一段SE配置
   
   继续往下翻复制第二段和第三段
   
   继续往下获取第四段
   

apiVersion: networking.istio.io/v1alpha3
kind: ServiceEntry
metadata:
  name: cnn
spec:
  hosts:
  - edition.cnn.com
  ports:
  - number: 80
    name: http-port
    protocol: HTTP
  - number: 443
    name: https
    protocol: HTTPS
  resolution: DNS
---
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: istio-egressgateway
spec:
  selector:
    istio: egressgateway
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - edition.cnn.com
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: egressgateway-for-cnn
spec:
  host: istio-egressgateway.istio-system.svc.cluster.local
  subsets:
  - name: cnn
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: direct-cnn-through-egress-gateway
spec:
  hosts:
  - edition.cnn.com
  gateways:
  - istio-egressgateway
  - mesh
  http:
  - match:
    - gateways:
      - mesh
      port: 80
    route:
    - destination:
        host: istio-egressgateway.istio-system.svc.cluster.local
        subset: cnn
        port:
          number: 80
      weight: 100
  - match:
    - gateways:
      - istio-egressgateway
      port: 80
    route:
    - destination:
        host: edition.cnn.com
        port:
          number: 80
      weight: 100

2.3 整理yaml

这里修改内容比较多不要遗漏
域名可以用vi的替换进行批量修改

1. 按esc
2. 输入 “:%s#edition.cnn.com#example.org#g”
   当然手动改也是可以的

apiVersion: networking.istio.io/v1alpha3
kind: ServiceEntry
metadata:
  name: cnn
  namespace: egress		#
spec:
  hosts:
  - example.org			#
  ports:
  - number: 80
    name: http-port
    protocol: HTTP
  resolution: DNS
---
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: exampleorg-egress		#
  namespace: egress				#
spec:
  selector:
    istio: egressgateway		#
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - example.org				#
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: egressgateway-for-cnn
  namespace: egress				#
spec:
  host: istio-egressgateway.istio-system.svc.cluster.local
  subsets:
  - name: cnn
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: direct-cnn-through-egress-gateway
  namespace: egress				#
spec:
  hosts:
  - example.org					#
  gateways:
  - exampleorg-egress			#这里千万别漏改
  - mesh
  http:
  - match:
    - gateways:
      - mesh
      port: 80
    route:
    - destination:
        host: istio-egressgateway.istio-system.svc.cluster.local
        subset: cnn
        port:
          number: 80
      weight: 100
  - match:
    - gateways:
      - exampleorg-egress		#这里千万别漏改
      port: 80
    route:
    - destination:
        host: example.org		#
        port:
          number: 80
      weight: 100

部署应用

kubectl  apply -f 2-6.yaml

3. 测试

在egress ns下创建一个测试的pod

kubectl run --image nginx:1.25 test -n egress

通过该pod访问example.org

kubectl exec -n egress test -- curl -I example.org

查看测试pod的日志

kubectl logs -n egress test |tail -5

可以看到并不是直接从它上面出去的
再查看sidecar的日志,可以看到是由sidecar发起的

kubectl  logs -n egress test -c istio-proxy|tail -5

再查看istio-egress的日志

kubectl logs -n istio-system istio-egressgateway-56c98656d-wnqv2 |tail -5

可以看到最后一条就是访问example.org的

至此此题配置测试完毕,这题是整个考试中最复杂的一题,其实修改的内容也不是特别多,且模板内容都在同一个页面的连续位置上.所以熟悉了之后也就这样.