说明：本文在bookinfo部署完成的基础上操作，当前服务都为v1版本
一：更新目的，最终将reviews服务从v1更新到v2
1：先将10%的流量更新到v2,90%的还在v1
2：将转发到v2的流量增加到50%，v1的减少到50%
3：全部流程转发到v2，v1没有流量
4：将50流量转发到v2,50%到v3
5：将流量全部转发到
部署目标路由规则
destination-rule-all.yaml
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: productpage
spec:
host: productpage
subsets:
- name: v1
labels:
version: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- name: v1
labels:
version: v1
- name: v2
labels:
version: v2
- name: v3
labels:
version: v3
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: ratings
spec:
host: ratings
subsets:
- name: v1
labels:
version: v1
- name: v2
labels:
version: v2
- name: v2-mysql
labels:
version: v2-mysql
- name: v2-mysql-vm
labels:
version: v2-mysql-vm
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: details
spec:
host: details
subsets:
- name: v1
labels:
version: v1
- name: v2
labels:
version: v2
---
准备第1步的清单文件
virtual-service-reviews-90-10.yaml
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v1
weight: 90
- destination:
host: reviews
subset: v2
weight: 10
现象：刷新页面，reviews v1和v2出现频率大概为9:1
准备第2步的清单文件
virtual-service-reviews-50.yaml
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v1
weight: 50
- destination:
host: reviews
subset: v2
weight: 50
现象：刷新页面，v1和v2出现频率大概1:1
准备第3步清单文件
virtual-service-reviews-v2.yaml
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v2
现象：刷新页面，reviews版本全为v2
准备第4步的清单文件
virtual-service-reviews-v2-v3.yaml
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v2
weight: 50
- destination:
host: reviews
subset: v3
weight: 50
现象：刷新页面，v2 和v3页面出现频率大概为1:1
准备第5步的清单文件
virtual-service-reviews-v3.yaml
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v3
现象：刷新页面，全部为v3页面
