10 个 Istio 流量管理 最常用的例子,强烈建议收藏起来,以备不时之需。
为了方便理解,以Istio官方提供的Bookinfo应用示例为例,引出 Istio 流量管理的常用例子。
Bookinfo应用的架构图如下:
其中,包含四个单独的微服务:
productpage
:调用details
和reviews
两个服务,用来生成页面。details
:包含了书籍的信息。reviews
:包含了书籍相关的评论。它还会调用 ratings 微服务。rating
:包含了由书籍评价组成的评级信息。
其中,reviews
服务有 3 个版本:
- v1 版本不会调用
ratings
服务。 - v2 版本会调用
ratings
服务,并使用 1 到 5 个黑色星形图标来显示评分信息。 - v3 版本会调用
ratings
服务,并使用 1 到 5 个红色星形图标来显示评分信息。
流量转移
代码语言:javascript复制目标1:把
reviews
服务的所有流量都路由到v1版本。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
代码语言:javascript复制目标2:把
reviews
服务的50%流量转移到v3版本。
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: v3
weight: 50
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
代码语言:javascript复制目标3:把
reviews
服务的所有流量都路由到v3版本。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v3
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
基于用户身份的路由
目标:来自名为 OneMore 的用户的所有流量都路由到v2版本,其他流量都路由到v1版本。
Istio 对用户身份没有任何特殊的内置机制。在应用示例中,productpage
服务在所有到 reviews
服务的 HTTP 请求中都增加了一个自定义的 end-user
请求头,其值为用户名。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- match:
- headers:
end-user:
exact: OneMore
route:
- destination:
host: reviews
subset: v2
- route:
- destination:
host: reviews
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
注入 HTTP 延迟故障
代码语言:javascript复制目标:用户 OneMore 访问时,
ratings
服务注入一个 2 秒的延迟,productpage
页面在大约 2 秒钟加载完成并且没有错误。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: ratings
spec:
hosts:
- ratings
http:
- match:
- headers:
end-user:
exact: OneMore
fault:
delay:
percentage:
value: 100.0
fixedDelay: 2s
route:
- destination:
host: ratings
subset: v1
- route:
- destination:
host: ratings
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: ratings
spec:
host: ratings
subsets:
- labels:
version: v1
name: v1
注入 HTTP 中止故障
代码语言:javascript复制目标:用户 OneMore 访问时,
ratings
服务注入一个503的中止故障,productpage
页面能够立即被加载,同时显示 “Ratings service is currently unavailable” 这样的消息。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: ratings
spec:
hosts:
- ratings
http:
- fault:
abort:
httpStatus: 503
percentage:
value: 100
match:
- headers:
end-user:
exact: OneMore
route:
- destination:
host: ratings
subset: v1
- route:
- destination:
host: ratings
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: ratings
spec:
host: ratings
subsets:
- labels:
version: v1
name: v1
设置请求超时
首先,用户 OneMore 访问时, ratings
服务注入一个 2 秒的延迟,productpage
页面在大约 2 秒钟加载完成并且没有错误。
按照上文注入 HTTP 延迟故障进行操作,不再赘述。
代码语言:javascript复制目标:用户 OneMore 访问时,
reviews
服务的请求超时设置为 1 秒,同时显示 “Sorry, product reviews are currently unavailable for this book.” 这样的消息。
kind: VirtualService
apiVersion: networking.istio.io/v1alpha3
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- match:
- headers:
end-user:
exact: OneMore
route:
- destination:
host: reviews
subset: v2
timeout: 1s
- route:
- destination:
host: reviews
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
在Jaeger可以看到具体的调用链如下:
设置请求重试
首先,用户 OneMore 访问时, ratings
服务注入一个 2 秒的延迟,productpage
页面在大约 2 秒钟加载完成并且没有错误。
按照上文注入 HTTP 延迟故障进行操作,不再赘述。
代码语言:javascript复制目标:用户 OneMore 访问时,
reviews
服务的请求重试次数为2次,重试超时时间为 0.5 秒,同时显示 “Sorry, product reviews are currently unavailable for this book.” 这样的错误消息。
kind: VirtualService
apiVersion: networking.istio.io/v1alpha3
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- match:
- headers:
end-user:
exact: OneMore
route:
- destination:
host: reviews
subset: v2
retries:
attempts: 2
perTryTimeout: 0.5s
- route:
- destination:
host: reviews
subset: v1
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
拒绝目标IP的请求
代码语言:javascript复制目标:除了IP为
10.201.240.131
的客户端可以访问/api/v1/products/1
,其他客户端拒绝请求。
apiVersion: security.istio.io/v1beta1
kind: AuthorizationPolicy
metadata:
name: deny-by-ip
spec:
selector:
matchLabels:
app: productpage
action: DENY
rules:
- to:
- operation:
paths: ["/api/v1/products/1"]
when:
- key: remote.ip
notValues: ["10.201.240.131"]
熔断
代码语言:javascript复制目标:设置
details
服务的并发上限为1。
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: details
spec:
host: details
trafficPolicy:
connectionPool:
tcp:
maxConnections: 1
http:
http1MaxPendingRequests: 1
maxRequestsPerConnection: 1
可以使用 Fortio 进行负载测试,发送并发数为 2 的连接(-c 2
),请求 20 次(-n 2
0):
kubectl exec fortio-deploy-684b6b47f8-tzsg8 -c fortio -- /usr/bin/fortio load -c -qps -n -loglevel Warning http://details:9080/details/0
其中,fortio-deploy-684b6b47f8-tzsg8是Fortio的Pod名称,效果如下:
流量镜像
代码语言:javascript复制目标:把流量全部路由到reviews服务的 v2 版本,再把流量全部镜像到 v3 版本。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: reviews
spec:
hosts:
- reviews
http:
- route:
- destination:
host: reviews
subset: v2
mirror:
host: reviews
subset: v3
mirrorPercentage:
value: 100.0
---
apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
name: reviews
spec:
host: reviews
subsets:
- labels:
version: v1
name: v1
- labels:
version: v2
name: v2
- labels:
version: v3
name: v3
执行如下命令查看reviews
服务 v3 版本的 Envoy 访问日志:
kubectl logs -l app=reviews,version=v3 -c istio-proxy
可以看到reviews
服务 v3 版本被调用的日志:
{
"authority": "reviews-shadow:9080",
"bytes_received": ,
"bytes_sent": ,
"connection_termination_details": null,
"downstream_local_address": "10.1.1.64:9080",
"downstream_remote_address": "10.1.1.59:0",
"duration": ,
"method": "GET",
"path": "/reviews/0",
"protocol": "HTTP/1.1",
"request_id": "b79cefe6-1277-9c39-b398-f94a704840cc",
"requested_server_name": "outbound_.9080_.v3_.reviews.default.svc.cluster.local",
"response_code": ,
"response_code_details": "via_upstream",
"response_flags": "-",
"route_name": "default",
"start_time": "2022-06-27T07:34:19.129Z",
"upstream_cluster": "inbound|9080||",
"upstream_host": "10.1.1.64:9080",
"upstream_local_address": "127.0.0.6:59837",
"upstream_service_time": "1913",
"upstream_transport_failure_reason": null,
"user_agent": "curl/7.79.1",
"x_forwarded_for": "10.1.1.59"
}
Ingress的路由
代码语言:javascript复制目标:请求头
app-id
为details
的所有流量都路由到details
服务中。
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: bookinfo
spec:
hosts:
- '*'
gateways:
- bookinfo-gateway
http:
- match:
- uri:
exact: /productpage
- uri:
prefix: /static
- uri:
exact: /login
- uri:
exact: /logout
- uri:
prefix: /api/v1/products
route:
- destination:
host: productpage
port:
number: 9080
- match:
- headers:
app-id:
exact: details
route:
- destination:
host: details
port:
number: 9080
使用curl命令验证一下:
代码语言:javascript复制curl -H "app-id: details" -v http://127.0.0.1/details/2
返回结果如下:
代码语言:javascript复制* Trying 127.0.0.1:80...
* Connected to 127.0.0.1 (127.0.0.1) port (#)
> GET /details/ HTTP/1.1
> Host: 127.0.0.1
> User-Agent: curl/7.79.1
> Accept: */*
> app-id: details
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 OK
< content-type: application/json
< server: istio-envoy
< date: Tue, Jun :: GMT
< content-length:
< x-envoy-upstream-service-time:
<
{"id":,"author":"William Shakespeare","year":,"type":"paperback","pages":,"publisher":"PublisherA","language":"English","ISBN-10":"1234567890","ISBN-13":"123-1234567890"}
* Connection # to host 127.0.0.1 left intact
返回结果可以看出,访问的是details
服务。