Istio的流量管理(实操二)
涵盖官方文档Traffic Management章节中的inrgess部分。
@H_502_6@目录
在kubernetes环境中，kubernetes ingress资源用于指定暴露到集群外的服务。在istio服务网格中，使用了一种不同的配置模型，称为istio网关。一个网关允许将istio的特性，如镜像和路由规则应用到进入集群的流量上。
本节描述了如何使用istio网关将一个服务暴露到服务网格外。
使用如下命令创建httpbin服务
$ kubectl apply -f samples/httpbin/httpbin.yaml
由于本环境中没有配置对外的负载均衡，因此此处的EXTERNAL-IP为空，使用node port进行访问
# kubectl get svc istio-ingressgateway -n istio-system
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
istio-ingressgateway LoadBalancer 10.84.93.45 <pending> ... 11d
获取ingressgateway service的http2和https对应的端口
$ export INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="http2")].nodePort}')
$ export SECURE_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="https")].nodePort}')
$ export TCP_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="tcp")].nodePort}')
下面是istio-system命名空间的istio-ingressgateway service中的一部分端口信息，可以看到http2和https的nodeport分别为31194和31785，对应上面的INGRESS_PORT和SECURE_INGRESS_PORT
{
"name": "http2","nodePort": 31194,"port": 80,"protocol": "TCP","targetPort": 80
},{
"name": "https","nodePort": 31785,"port": 443,"targetPort": 443
},获取istio-system命名空间中ingressgateway pod 的hostIP
$ export INGRESS_HOST=$(kubectl get po -l istio=ingressgateway -n istio-system -o jsonpath='{.items[0].status.hostIP}')
一个ingress网关描述了在网格边缘用于接收入站HTTP/TCP连接的负载均衡，配置了暴露的端口，协议等。kubernetes ingress资源不包括任何流量路由配置。ingress 流量的路由使用istio路由规则，与内部服务请求相同：
创建istio Gateway，网关监听地址为httpbin.example.com，端口为80(位于默认的ingressgatewaypod中)
kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: httpbin-gateway
spec:
selector:
istio: ingressgateway # use Istio default gateway implementation
servers:
- port:
number: 80 #gateway暴露80端口
name: http
protocol: HTTP
hosts: #gateway暴露的主机名
- "httpbin.example.com"
EOF
通过Gateway配置进入的流量路由，将URI为httpbin.example.com，且目的地为/status或/delay的请求分发到httpbin服务的8000端口，其他请求会返回404响应。
kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
Metadata:
name: httpbin
spec:
hosts: #virtual service的hosts字段与Gateway的servers.hosts字段需要匹配
- "httpbin.example.com"
gateways:
- httpbin-gateway
http:
- match:
- uri:
prefix: /status
- uri:
prefix: /delay
route:
- destination:
port:
number: 8000
host: httpbin
EOF
可以看到流量被导入了httpbin service暴露的8000端口上
$ oc get svc |grep httpbin
httpbin ClusterIP 10.84.222.69 <none> 8000/TCP 19h
来自网格内部其他服务的请求则不受此规则的约束，会使用默认的轮询路由进行请求分发。为了限制内部的调用规则，可以将特定的值
mesh添加到gateways列表中。由于内部服务主机名(如httpbin.default.svc.cluster.local) 可能与外部不同，因此需要将主机名添加到hosts列表中。
使用curl命令访问httpbin服务，此时通过-H选项修改了HTTP请求首部的Host字段，使用http2的nodeport方式访问：
$ curl -s -I -HHost:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/status/200
HTTP/1.1 200 OK
server: istio-envoy
date: Thu,21 May 2020 03:22:50 GMT
content-type: text/html; charset=utf-8
access-control-allow-origin: *
access-control-allow-credentials: true
content-length: 0
x-envoy-upstream-service-time: 21
访问其他URL路径则返回404错误
$ curl -s -I -HHost:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/headers
HTTP/1.1 404 Not Found
date: Thu,21 May 2020 03:25:20 GMT
server: istio-envoy
transfer-encoding: chunked
由于无法像使用curl一样修改请求的Host首部字段，因此无法使用浏览器访问httpbin服务。为了解决这个问题，可以在Gateway和VirtualService中的host字段使用通配符*。
$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: httpbin-gateway
spec:
selector:
istio: ingressgateway # use Istio default gateway implementation
servers:
- port:
number: 80
name: http
protocol: HTTP
hosts:
- "*" #指定通配符，监听所有流量，不限制外部流量的地址
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
Metadata:
name: httpbin
spec:
hosts:
- "*"
gateways:
- httpbin-gateway
http:
- match:
- uri:
prefix: /headers
route:
- destination:
port:
number: 8000
host: httpbin
EOF
检查环境变量INGRESS_HOST和INGRESS_PORT，保证这两个值是有效的
$ kubectl get svc -n istio-system
$ echo INGRESS_HOST=$INGRESS_HOST,INGRESS_PORT=$INGRESS_PORT
校验相同的端口上没有其他istio ingress网格
$ kubectl get gateway --all-namespaces
校验没有在相同的IP和端口上定义kubernetes ingress资源
$ kubectl get ingress --all-namespaces
如果没有负载均衡，可以参照上面步骤使用node port方式
$ kubectl delete gateway httpbin-gateway
$ kubectl delete virtualservice httpbin
$ kubectl delete --ignore-not-found=true -f samples/httpbin/httpbin.yaml
执行ingress流量控制中的Before you begin和Determining the ingress IP and ports小节的操作，部署httpbin服务。本节介绍如何通过kubernetes的Ingress(非istio的gateway)进行访问。
下面展示如何配置一个80端口的Ingress，用于HTTP流量：
创建一个istio Gateway，将来自httpbin.example.com:80/status/*的流量分发到service httpbin的8000端口
$ kubectl apply -f - <<EOF
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
Metadata:
annotations:
kubernetes.io/ingress.class: istio
name: ingress
spec:
rules:
- host: httpbin.example.com
http:
paths:
- path: /status/*
backend:
serviceName: httpbin
servicePort: 8000
EOF
注意需要使用 kubernetes.io/ingress.class annotation来告诉istio网关控制器处理该ingress，否则会忽略该ingress。
使用curl命令访问httpbin服务。Ingress的流量也需要经过istio ingressgateway。
$ curl -I -HHost:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/status/200
HTTP/1.1 200 OK
server: istio-envoy
date: Fri,22 May 2020 06:12:56 GMT
content-type: text/html; charset=utf-8
access-control-allow-origin: *
access-control-allow-credentials: true
content-length: 0
x-envoy-upstream-service-time: 20
httpbin的服务发现是通过EDS实现的，使用如下命令查看：
$ istioctl proxy-config cluster istio-ingressgateway-569669bb67-b6p5r|grep 8000
httpbin.default.svc.cluster.local 8000 - outbound EDS
outbound_.8000_._.httpbin.default.svc.cluster.local - - - EDS
访问其他未暴露的路径，返回HTTP 404错误：
$ curl -I -HHost:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/headers
HTTP/1.1 404 Not Found
date: Fri,22 May 2020 06:24:30 GMT
server: istio-envoy
transfer-encoding: chunked
Ingress支持TLS设置。Istio也支持TLS设置，但相关的secret必须存在istio-ingressgateway deployment所在的命名空间中。可以使用cert-manager生成这些证书。
默认情况下，Istio会将路径视为完全匹配，如果路径使用/*或*结尾，则该路径为前缀匹配。不支持其他正则匹配。
kubernetes 1.18中新增了一个字段pathType，允许声明为Exact或Prefix。
IngressClass
kubernetes 1.18中新增了一个资源IngressClass，替换了Ingress资源的 kubernetes.io/ingress.class annotation。如果使用该资源，则需要将controller设置为istio.io/ingress-controller：
apiVersion: networking.k8s.io/v1beta1
kind: IngressClass
Metadata:
name: istio
spec:
controller: istio.io/ingress-controller
---
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
Metadata:
name: ingress
spec:
ingressClassName: istio
...
$ kubectl delete ingress ingress
$ kubectl delete --ignore-not-found=true -f samples/httpbin/httpbin.yaml
本节讲述如何使用simple或mutual TLS暴露安全的HTTPS服务。证书是通过SDS进行密钥发现的。
TLS需要的私钥，服务端证书，根证书是使用基于文件装载的方法配置的。
执行ingress流量控制中的Before you begin和Determining the ingress IP and ports小节的操作，部署httpbin服务，并获取 INGRESS_HOST 和SECURE_INGRESS_PORT变量。
生成一个根证书和一个私钥，用于签名服务的证书
$ openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 -subj '/O=example Inc./CN=example.com' -keyout example.com.key -out example.com.crt
为 httpbin.example.com生成一个证书和私钥
$ openssl req -out httpbin.example.com.csr -newkey rsa:2048 -nodes -keyout httpbin.example.com.key -subj "/CN=httpbin.example.com/O=httpbin organization"
$ openssl x509 -req -days 365 -CA example.com.crt -CAkey example.com.key -set_serial 0 -in httpbin.example.com.csr -out httpbin.example.com.crt
为ingree网关创建一个secret
secret的名字不能以
istio或prometheus开头，且secret不应该包含token字段
$ kubectl create -n istio-system secret tls httpbin-credential --key=httpbin.example.com.key --cert=httpbin.example.com.crt
在server部分定义一个443端口的Gateway，将credentialName指定为httpbin-credential，与secret的名字相同，TLS的mode为SIMPLE。
$ cat <<EOF | kubectl apply -f -
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: mygateway
spec:
selector:
istio: ingressgateway # use istio default ingress gateway
servers:
- port:
number: 443
name: https
protocol: HTTPS
tls: #对暴露的服务使用SIMPLE模式的tls，即单向tls验证
mode: SIMPLE
credentialName: httpbin-credential # must be the same as secret
hosts:
- httpbin.example.com
EOF
配置进入Gateway的流量路由。与上一节中的VirtualService相同
$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
Metadata:
name: httpbin
spec:
hosts:
- "httpbin.example.com"
gateways:
- httpbin-gateway
http:
- match:
- uri:
prefix: /status
- uri:
prefix: /delay
route:
- destination:
port:
number: 8000 #可以看到tls只是这是在gateway上的，当进入网格之后就不需要了
host: httpbin
EOF
使用curl向SECURE_INGRESS_PORT发送HTTPS请求访问httpbin服务，请求中携带了公钥example.com.crt 。--resolve标记可以在使用curl访问TLS的网关IP时，在SNI中支持httpbin.example.com。--cacert选择支持使用生成的证书校验服务。
-HHost:httpbin.example.com选项仅在SECURE_INGRESS_PORT不同于实际的网关端口(443)时才会需要，例如，通过映射的NodePort方式访问服务时。
通过将请求发送到/status/418 URL路径时，可以看到httpbin确实被访问了，httpbin服务会返回418 I’m a Teapot代码。.
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
--cacert example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
> --cacert example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
* Added httpbin.example.com:31967:172.20.127.211 to DNS cache
* About to connect() to httpbin.example.com port 31967 (#0)
* Trying 172.20.127.211...
* Connected to httpbin.example.com (172.20.127.211) port 31967 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* CAfile: example.com.crt
CApath: none
* SSL connection using TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
* Server certificate:
* subject: O=httpbin organization,CN=httpbin.example.com
* start date: May 22 09:03:01 2020 GMT
* expire date: May 22 09:03:01 2021 GMT
* common name: httpbin.example.com
* issuer: CN=example.com,O=example Inc.
> GET /status/418 HTTP/1.1
> User-Agent: curl/7.29.0
> Accept: */*
> Host:httpbin.example.com
>
< HTTP/1.1 418 Unknown
< server: istio-envoy
< date: Fri,22 May 2020 09:08:29 GMT
< x-more-info: http://tools.ietf.org/html/rfc2324
< access-control-allow-origin: *
< access-control-allow-credentials: true
< content-length: 135
< x-envoy-upstream-service-time: 2
<
-=[ teapot ]=-
_...._
.' _ _ `.
| ."` ^ `". _,\_;`"---"`|//
| ;/
\_ _/
`"""`
* Connection #0 to host httpbin.example.com left intact
删除老的网关secret，创建一个新的secret，并使用该secret修改ingress网关的凭据
$ kubectl -n istio-system delete secret httpbin-credential
$ mkdir new_certificates
$ openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 -subj '/O=example Inc./CN=example.com' -keyout new_certificates/example.com.key -out new_certificates/example.com.crt
$ openssl req -out new_certificates/httpbin.example.com.csr -newkey rsa:2048 -nodes -keyout new_certificates/httpbin.example.com.key -subj "/CN=httpbin.example.com/O=httpbin organization"
$ openssl x509 -req -days 365 -CA new_certificates/example.com.crt -CAkey new_certificates/example.com.key -set_serial 0 -in new_certificates/httpbin.example.com.csr -out new_certificates/httpbin.example.com.crt
$ kubectl create -n istio-system secret tls httpbin-credential \
--key=new_certificates/httpbin.example.com.key \
--cert=new_certificates/httpbin.example.com.crt
使用新的证书链访问httpbin服务
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
--cacert new_certificates/example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
如果使用老的证书访问，则返回错误
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
> --cacert example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
* Added httpbin.example.com:31967:172.20.127.211 to DNS cache
* About to connect() to httpbin.example.com port 31967 (#0)
* Trying 172.20.127.211...
* Connected to httpbin.example.com (172.20.127.211) port 31967 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* CAfile: example.com.crt
CApath: none
* Server certificate:
* subject: O=httpbin organization,CN=httpbin.example.com
* start date: May 22 09:24:07 2020 GMT
* expire date: May 22 09:24:07 2021 GMT
* common name: httpbin.example.com
* issuer: CN=example.com,O=example Inc.
* NSS error -8182 (SEC_ERROR_BAD_SIGNATURE)
* Peer's certificate has an invalid signature.
* Closing connection 0
curl: (60) Peer's certificate has an invalid signature.
本节会为多个主机(httpbin.example.com和helloworld-v1.example.com)配置一个ingress网关。ingress网关会在credentialName中查找唯一的凭据。
删除之前创建的secret并为httpbin重建凭据
$ kubectl -n istio-system delete secret httpbin-credential
$ kubectl create -n istio-system secret tls httpbin-credential \
--key=httpbin.example.com.key \
--cert=httpbin.example.com.crt
启动helloworld-v1
$ cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Service
Metadata:
name: helloworld-v1
labels:
app: helloworld-v1
spec:
ports:
- name: http
port: 5000
selector:
app: helloworld-v1
---
apiVersion: apps/v1
kind: Deployment
Metadata:
name: helloworld-v1
spec:
replicas: 1
selector:
matchLabels:
app: helloworld-v1
version: v1
template:
Metadata:
labels:
app: helloworld-v1
version: v1
spec:
containers:
- name: helloworld
image: istio/examples-helloworld-v1
resources:
requests:
cpu: "100m"
imagePullPolicy: IfNotPresent #Always
ports:
- containerPort: 5000
EOF
为helloworld-v1.example.com创建证书和私钥
$ openssl req -out helloworld-v1.example.com.csr -newkey rsa:2048 -nodes -keyout helloworld-v1.example.com.key -subj "/CN=helloworld-v1.example.com/O=helloworld organization"
$ openssl x509 -req -days 365 -CA example.com.crt -CAkey example.com.key -set_serial 1 -in helloworld-v1.example.com.csr -out helloworld-v1.example.com.crt
为helloworld-credential创建secret
$ kubectl create -n istio-system secret tls helloworld-credential --key=helloworld-v1.example.com.key --cert=helloworld-v1.example.com.crt
定义一个网关，网关端口为443。在credentialName字段分别设置httpbin-credential和helloworld-credential，TLS模式为SIMPLE。
$ cat <<EOF | kubectl apply -f -
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: mygateway
spec:
selector:
istio: ingressgateway # use istio default ingress gateway
servers:
- port:
number: 443
name: https-httpbin #httpbin的gateway配置
protocol: HTTPS
tls:
mode: SIMPLE
credentialName: httpbin-credential
hosts:
- httpbin.example.com
- port:
number: 443
name: https-helloworld #https-helloword的gateway配置
protocol: HTTPS
tls:
mode: SIMPLE
credentialName: helloworld-credential
hosts:
- helloworld-v1.example.com
EOF
配置gateway的流量路由，为新应用添加对应的virtual service
$ cat <<EOF | kubectl apply -f -
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
Metadata:
name: helloworld-v1
spec:
hosts:
- helloworld-v1.example.com
gateways:
- mygateway
http:
- match:
- uri:
exact: /hello
route:
- destination:
host: helloworld-v1
port:
number: 5000
EOF
向helloworld-v1.example.com发送HTTPS请求
$ curl -v -HHost:helloworld-v1.example.com --resolve "helloworld-v1.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
--cacert example.com.crt "https://helloworld-v1.example.com:$SECURE_INGRESS_PORT/hello"
...
< HTTP/1.1 200 OK
< content-type: text/html; charset=utf-8
< content-length: 60
< server: istio-envoy
< date: Sat,23 May 2020 07:38:40 GMT
< x-envoy-upstream-service-time: 143
<
Hello version: v1,instance: helloworld-v1-5dfcf5d5cd-2l44c
* Connection #0 to host helloworld-v1.example.com left intact
向 httpbin.example.com发送请求
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
--cacert example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
...
-=[ teapot ]=-
_...._
.' _ _ `.
| ."` ^ `". _,\_;`"---"`|//
| ;/
\_ _/
`"""`
* Connection #0 to host httpbin.example.com left intact
删除之前的secreting创建一个新的secret，server会使用该CA证书校验client，使用cacert保存CA证书。
$ kubectl -n istio-system delete secret httpbin-credential
$ kubectl create -n istio-system secret generic httpbin-credential --from-file=tls.key=httpbin.example.com.key \
--from-file=tls.crt=httpbin.example.com.crt --from-file=ca.crt=example.com.crt
将gateway的TLS模式设置为MUTUAL
$ cat <<EOF | kubectl apply -f -
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: mygateway
spec:
selector:
istio: ingressgateway # use istio default ingress gateway
servers:
- port:
number: 443
name: https
protocol: HTTPS
tls:
mode: MUTUAL #对网关暴露的服务httpbin.example.com启用双向认证
credentialName: httpbin-credential # must be the same as secret
hosts:
- httpbin.example.com
EOF
使用先前的方式发送HTTPS请求，可以看到访问失败
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" \
> --cacert example.com.crt "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
* Added httpbin.example.com:31967:172.20.127.211 to DNS cache
* About to connect() to httpbin.example.com port 31967 (#0)
* Trying 172.20.127.211...
* Connected to httpbin.example.com (172.20.127.211) port 31967 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* CAfile: example.com.crt
CApath: none
* NSS: client certificate not found (nickname not specified)
* NSS error -12227 (SSL_ERROR_HANDSHAKE_FAILURE_ALERT)
* SSL peer was unable to negotiate an acceptable set of security parameters.
* Closing connection 0
curl: (35) NSS: client certificate not found (nickname not specified)
使用公钥example.com.crt生成client的证书和私钥。在curl中传入客户端的证书和私钥，使用--cert传入客户端证书，使用--key传入私钥
$ openssl req -out client.example.com.csr -newkey rsa:2048 -nodes -keyout client.example.com.key -subj "/CN=client.example.com/O=client organization"
$ openssl x509 -req -days 365 -CA example.com.crt -CAkey example.com.key -set_serial 1 -in client.example.com.csr -out client.example.com.crt
$ curl -v -HHost:httpbin.example.com --resolve "httpbin.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST" --cacert example.com.crt --cert ./client.example.com.crt --key ./client.example.com.key "https://httpbin.example.com:$SECURE_INGRESS_PORT/status/418"
...
-=[ teapot ]=-
_...._
.' _ _ `.
| ."` ^ `". _,\_;`"---"`|//
| ;/
\_ _/
`"""`
* Connection #0 to host httpbin.example.com left intact
istio支持几种不同的Secret格式，来支持与多种工具的集成，如cert-manager:
tls.key和tls.crt；对于mutual TLS，会用到ca.crt
key和cert；对于mutual TLS，会用到cacert
key和cert；对于mutual TLS，会用到一个单独的名为 <secret>-cacert的generic Secret，以及一个cacert key。例如httpbin-credential 包含key 和cert，httpbin-credential-cacert 包含cacert
检查INGRESS_HOST和SECURE_INGRESS_PORT环境变量
$ kubectl get svc -n istio-system
$ echo INGRESS_HOST=$INGRESS_HOST,SECURE_INGRESS_PORT=$SECURE_INGRESS_PORT
检查istio-ingressgateway控制器的错误日志
$ kubectl logs -n istio-system "$(kubectl get pod -l istio=ingressgateway \
-n istio-system -o jsonpath='{.items[0].Metadata.name}')"
校验istio-system命名空间中成功创建了secret。上例中应该存在httpbin-credential和helloworld-credential
$ kubectl -n istio-system get secrets
校验ingress网关agent将密钥/证书对上传到了ingress网关
$ kubectl logs -n istio-system "$(kubectl get pod -l istio=ingressgateway \
-n istio-system -o jsonpath='{.items[0].Metadata.name}')"
校验CA加载到了 istio-ingressgateway pod中，查看是否存在example.com.crt
$ kubectl exec -it -n istio-system $(kubectl -n istio-system get pods -l istio=ingressgateway -o jsonpath='{.items[0].Metadata.name}') -- ls -al /etc/istio/ingressgateway-ca-certs
如果创建了istio-ingressgateway-ca-certs secret，但没有加载CA证书，删除ingress网关pod，强制加载该证书
$ kubectl delete pod -n istio-system -l istio=ingressgateway
校验CA证书的Subject字段是否正确
$ kubectl exec -i -n istio-system $(kubectl get pod -l istio=ingressgateway -n istio-system -o jsonpath='{.items[0].Metadata.name}') -- cat /etc/istio/ingressgateway-ca-certs/example.com.crt | openssl x509 -text -noout | grep 'Subject:'
Subject: O=example Inc.,CN=example.com
log中可以看到添加了httpbin-credential secret。如果使用mutual TLS，那么也会出现 httpbin-credential-cacert secret。校验log中显示了网关agent从ingress网关接收到了SDS请求，资源的名称为 httpbin-credential，且ingress网关获取到了密钥/证书对。如果使用了mutual TLS，日志应该显示将密钥/证书发送到ingress网关，网关agent接收到了带 httpbin-credential-cacert 资源名称的SDS请求，并回去到了根证书。
删除Gateway配置，VirtualService和secret
$ kubectl delete gateway mygateway
$ kubectl delete virtualservice httpbin
$ kubectl delete --ignore-not-found=true -n istio-system secret httpbin-credential \
helloworld-credential
$ kubectl delete --ignore-not-found=true virtualservice helloworld-v1
删除证书目录
$ rm -rf example.com.crt example.com.key httpbin.example.com.crt httpbin.example.com.key httpbin.example.com.csr helloworld-v1.example.com.crt helloworld-v1.example.com.key helloworld-v1.example.com.csr client.example.com.crt client.example.com.csr client.example.com.key ./new_certificates
停止httpbin和helloworld-v1 服务：
$ kubectl delete deployment --ignore-not-found=true httpbin helloworld-v1
$ kubectl delete service --ignore-not-found=true httpbin helloworld-v1
上一节中描述了如何配置HTTPS ingree来访问一个HTTP服务。本节中描述如何配置HTTPS ingRSS来访问HTTPS服务等。通过配置ingress网关来执行SNI方式的访问，而不会在请求进入ingress时终止TLS。
本例中使用一个Nginx服务器作为HTTPS服务。
生成一个根证书和私钥，用于签名服务
$ openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 -subj '/O=example Inc./CN=example.com' -keyout example.com.key -out example.com.crt
为 Nginx.example.com创建证书和私钥
$ openssl req -out Nginx.example.com.csr -newkey rsa:2048 -nodes -keyout Nginx.example.com.key -subj "/CN=Nginx.example.com/O=some organization"
$ openssl x509 -req -days 365 -CA example.com.crt -CAkey example.com.key -set_serial 0 -in Nginx.example.com.csr -out Nginx.example.com.crt
创建kubernetes Secret保存服务的证书
$ kubectl create secret tls Nginx-server-certs --key Nginx.example.com.key --cert Nginx.example.com.crt
$ cat <<EOF > ./Nginx.conf
events {
}
http {
log_format main '$remote_addr - $remote_user [$time_local] $status '
'"$request" $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/Nginx/access.log main;
error_log /var/log/Nginx/error.log;
server {
listen 443 ssl;
root /usr/share/Nginx/html;
index index.html;
server_name Nginx.example.com;
ssl_certificate /etc/Nginx-server-certs/tls.crt;
ssl_certificate_key /etc/Nginx-server-certs/tls.key;
}
}
EOF
为Nginx服务创建kubernetes configmap
$ kubectl create configmap Nginx-configmap --from-file=Nginx.conf=./Nginx.conf
部署Nginx服务
$ cat <<EOF | istioctl kube-inject -f - | kubectl apply -f -
apiVersion: v1
kind: Service
Metadata:
name: my-Nginx
labels:
run: my-Nginx
spec:
ports:
- port: 443
protocol: TCP
selector:
run: my-Nginx
---
apiVersion: apps/v1
kind: Deployment
Metadata:
name: my-Nginx
spec:
selector:
matchLabels:
run: my-Nginx
replicas: 1
template:
Metadata:
labels:
run: my-Nginx
spec:
containers:
- name: my-Nginx
image: Nginx
ports:
- containerPort: 443
volumeMounts:
- name: Nginx-config
mountPath: /etc/Nginx
readOnly: true
- name: Nginx-server-certs
mountPath: /etc/Nginx-server-certs
readOnly: true
volumes:
- name: Nginx-config
configMap:
name: Nginx-configmap
- name: Nginx-server-certs
secret:
secretName: Nginx-server-certs #保存了Nginx服务的证书和私钥
EOF
为了测试Nginx服务部署成功，向服务发送不使用证书的方式请求，并校验打印信息是否正确：
$ kubectl exec -it $(kubectl get pod -l run=my-Nginx -o jsonpath={.items..Metadata.name}) -c istio-proxy -- curl -v -k --resolve
...
* Server certificate:
* subject: CN=Nginx.example.com; O=some organization
* start date: May 25 02:09:02 2020 GMT
* expire date: May 25 02:09:02 2021 GMT
* issuer: O=example Inc.; CN=example.com
* SSL certificate verify result: unable to get local issuer certificate (20),continuing anyway.
...
定义一个gateway，端口为443.注意TLS的模式为PASSTHROUGH，表示gateway会放行ingress流量，不终止TLS
$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
Metadata:
name: mygateway
spec:
selector:
istio: ingressgateway # use istio default ingress gateway
servers:
- port:
number: 443
name: https
protocol: HTTPS
tls:
mode: PASSTHROUGH #不终止TLS
hosts:
- Nginx.example.com
EOF
配置经过Gateway的流量路由
$ kubectl apply -f - <<EOF
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
Metadata:
name: Nginx
spec:
hosts:
- Nginx.example.com
gateways:
- mygateway
tls:
- match:
- port: 443 #将gateway的流量导入kubernetes的my-Nginx service
sniHosts:
- Nginx.example.com
route:
- destination:
host: my-Nginx
port:
number: 443
EOF
根据指导配置SECURE_INGRESS_PORT和INGRESS_HOST环境变量
通过ingress访问Nginx，可以看到访问成功
$ curl -v --resolve Nginx.example.com:$SECURE_INGRESS_PORT:$INGRESS_HOST --cacert example.com.crt https://Nginx.example.com:$SECURE_INGRESS_PORT
...
* SSL connection using TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
* Server certificate:
* subject: O=some organization,CN=Nginx.example.com
* start date: May 25 02:09:02 2020 GMT
* expire date: May 25 02:09:02 2021 GMT
* common name: Nginx.example.com
* issuer: CN=example.com,O=example Inc.
...
<title>Welcome to Nginx!</title>
...
移除kubernetes资源
$ kubectl delete secret Nginx-server-certs
$ kubectl delete configmap Nginx-configmap
$ kubectl delete service my-Nginx
$ kubectl delete deployment my-Nginx
$ kubectl delete gateway mygateway
$ kubectl delete virtualservice Nginx
删除证书和密钥
$ rm example.com.crt example.com.key Nginx.example.com.crt Nginx.example.com.key Nginx.example.com.csr
$ rm ./Nginx.conf
| Name | Description |
|---|---|
| PASSTHROUGH | 客户端提供的SNI字符串将用作VirtualService TLS路由中的匹配条件，以根据服务注册表确定目标服务 |
| SIMPLE | 使用标准TLS语义的安全连接 |
| MUTUAL | 通过提供服务器证书进行身份验证，使用双边TLS来保护与下游的连接 |
| AUTO_PASSTHROUGH | 与直通模式相似，不同之处在于具有此TLS模式的服务器不需要关联的VirtualService即可从SNI值映射到注册表中的服务。目标详细信息（例如服务/子集/端口）被编码在SNI值中。代理将转发到SNI值指定的上游（Envoy）群集（一组端点）。 |
| ISTIO_MUTUAL | 通过提供用于身份验证的服务器证书，使用相互TLS使用来自下游的安全连接 |
