Kubernetes集群 服务暴露 Nginx Ingress Controller
一、ingress控制器
1.1 ingress控制器作用
(类似于slb,做代理服务)
ingress controller可以为kubernetes 集群外用户访问Kubernetes集群内部pod提供代理服务。
- 提供全局访问代理
- 访问流程
- 用户–>ingress controller–>service–>pod
1.2 ingress控制器种类
1.2.1 Kubernetes Ingress Controller
-
参考链接:http://github.com/nginxinc/kubernetes-ingress
-
实现:Go/Lua(nginx 是用 C 写的)
-
许可证:Apache 2.0
-
Kubernetes 的“官方”控制器(之所以称为官方,是想把它区别于 NGINX 公司的控制器)。这是社区开发的控制器,它基于 nginx Web 服务器,并补充了一组用于实现额外功能的 Lua 插件。
-
由于 NGINX 十分流行,再加上把它用作控制器时所需的修改较少,它对于 K8s 普通工程师来说,可能是最简单和最直接的选择。
1.2.2 NGINX Ingress Controller
-
参考链接:http://github.com/kubernetes/ingress-nginx
-
实现:Go
-
许可证:Apache 2.0
-
这是 NGINX 公司开发的官方产品,它也有一个基于 NGINX Plus 的商业版。NGINX 的控制器具有很高的稳定性、持续的向后兼容性,且没有任何第三方模块。
-
由于消除了 Lua 代码,和官方控制器相比,它保证了较高的速度,但也因此受到较大限制。相较之下,它的付费版本有更广泛的附加功能,如实时指标、JWT 验证、主动健康检查等。
-
NGINX Ingress 重要的优势是对 TCP/UDP 流量的全面支持,最主要缺点是缺乏流量分配功能。
1.2.3 Kong Ingress
-
参考链接:http://github.com/Kong/kubernetes-ingress-controller
-
实现:Go
-
许可证:Apache 2.0
-
Kong Ingress 由 Kong Inc 开发,有两个版本:商业版和免费版。它基于 NGINX 构建,并增加了扩展其功能的 Lua 模块。
-
最初,Kong Ingress 主要用作 API 网关,用于 API 请求的处理和路由。现在,它已经成为成熟的 Ingress 控制器,主要优点是拥有大量易于安装和配置的附加模块、插件(包括第三方插件)。它开启了控制器具备大量附加功能的先河,其内置函数也提供了许多可能性。Kong Ingress 配置是用 CRD 执行的。
-
Kong Ingress 的一个重要特性是它只能在一个环境中运行(而不支持跨命名空间)。这是一个颇有争议的话题:有些人认为这是一个缺点,因为必须为每个环境生成实例;而另一些人认为这是一个特殊特性,因为它是更高级别的隔离,控制器故障的影响仅限于其所在的环境。
1.2.4 Traefik
-
参考链接:http://github.com/containous/traefik
-
实现:Go
-
许可证:MIT
-
最初,这个代理是为微服务请求及其动态环境的路由而创建的,因此具有许多有用的功能:连续更新配置(不重新启动)、支持多种负载均衡算法、Web UI、指标导出、对各种服务的支持协议、REST API、Canary 版本等。
-
支持开箱即用的 Let’s Encrypt 是它的另一个不错的功能,但它的主要缺点也很明显,就是为了控制器的高可用性,你必须安装并连接其 Key-value store。
-
在 2019 年 9 月发布的 Traefik v2.0 中,虽然它增加许多不错的新功能,如带有 SNI 的 TCP/SSL、金丝雀部署、流量镜像/shadowing 和经过改进的 Web UI,但一些功能(如 WAF 支持)还在策划讨论中。
-
与新版本同期推出的还有一个名叫 Mesh 的服务网格,它建在 Traefik 之上,对kubernetes内部服务访问做到受控及被监控。
1.2.5 HAProxy Ingress
-
参考链接:http://github.com/jcmoraisjr/haproxy-ingress
-
实现:Go(HAProxy 是用 C 写的)
-
许可证:Apache 2.0
-
HAProxy 是众所周知的代理服务器和负载均衡器。作为 Kubernetes 集群的一部分,它提供了“软”配置更新(无流量损失)、基于 DNS 的服务发现和通过 API 进行动态配置。 HAProxy 还支持完全自定义配置文件模板(通过替换 ConfigMap)以及在其中使用 Spring Boot 函数。
-
通常,工程师会把重点放在已消耗资源的高速、优化和效率上。而 HAProxy 的优点之一正是支持大量负载均衡算法。值得一提的是,在2020年 6 月发布的 v2.0 中,HAProxy 增加了许多新功能,其即将推出的 v2.1 有望带来更多新功能(包括 OpenTracing 支持)。
1.2.6 Voyager
-
参考链接:http://github.com/appscode/voyager
-
实现:Go
-
许可证:Apache 2.0
-
Voyager 基于 HAProxy,并作为一个通用的解决方案提供给大量供应商。它最具代表性的功能包括 L7 和 L4 上的流量负载均衡,其中,TCP L4 流量负载均衡称得上是该解决方案最关键的功能之一。
-
在2020年早些时候,尽管 Voyager 在 v9.0.0 中推出了对 HTTP/2 和 gRPC 协议的全面支持,但总的来看,对证书管理(Let’s Encrypt 证书)的支持仍是 Voyager 集成的最突出的新功能。
1.2.7 Contour
-
参考链接:http://github.com/heptio/contour
-
实现:Go
-
许可证:Apache 2.0
-
Contour 和 Envoy 由同一个作者开发,它基于 Envoy。它最特别的功能是可以通过 CRD(IngressRoute)管理 Ingress 资源,对于多团队需要同时使用一个集群的组织来说,这有助于保护相邻环境中的流量,使它们免受 Ingress 资源更改的影响。
-
它还提供了一组扩展的负载均衡算法(镜像、自动重复、限制请求率等),以及详细的流量和故障监控。对某些工程师而言,它不支持粘滞会话可能是一个严重缺陷。
1.2.8 Istio Ingress
-
参考链接:http://istio.io/docs/tasks/traffic-management/ingress
-
实现:Go
-
许可证:Apache 2.0
-
Istio 是 IBM、Google 和 Lyft 的联合开发项目,它是一个全面的服务网格解决方案——不仅可以管理所有传入的外部流量(作为 Ingress 控制器),还可以控制集群内部的所有流量。
-
Istio 将 Envoy 用作每种服务的辅助代理。从本质上讲,它是一个可以执行几乎所有操作的大型处理器,其中心思想是最大程度的控制、可扩展性、安全性和透明性。
-
通过 Istio Ingress,你可以对流量路由、服务之间的访问授权、均衡、监控、金丝雀发布等进行优化。
1.2.9 Ambassador
-
参考链接:http://github.com/datawire/ambassador
-
实现:Python
-
许可证:Apache 2.0
-
Ambassador 也是一个基于 Envoy 的解决方案,它有免费版和商业版两个版本。
-
Ambassador 被称为“Kubernetes 原生 API 微服务网关”,它与 K8s 原语紧密集成,拥有你所期望的从 Ingress controller 获得的功能包,它还可以与各种服务网格解决方案,如 Linkerd、Istio 等一起使用。
-
顺便提一下,Ambassador 博客日前发布了一份基准测试结果,比较了 Envoy、HAProxy 和 NGINX 的基础性能。
1.2.10 Gloo
-
参考链接:http://github.com/solo-io/gloo
-
实现:Go
-
许可证:Apache 2.0
-
Gloo 是在 Envoy 之上构建的新软件(于 2018 年 3 月发布),由于它的作者坚持认为“网关应该从功能而不是服务中构建 API”,它也被称为“功能网关”。其“功能级路由”的意思是它可以为后端实现是微服务、无服务器功能和遗留应用的混合应用路由流量。
-
由于拥有可插拔的体系结构,Gloo 提供了工程师期望的大部分功能,但是其中一些功能仅在其商业版本(Gloo Enterprise)中可用。
1.2.11 Skipper
-
参考链接:http://github.com/zalando/skipper
-
实现:Go
-
许可证:Apache 2.0
-
Skipper 是 HTTP 路由器和反向代理,因此不支持各种协议。从技术上讲,它使用 Endpoints API(而不是 Kubernetes Services)将流量路由到 Pod。它的优点在于其丰富的过滤器集所提供的高级 HTTP 路由功能,工程师可以借此创建、更新和删除所有 HTTP 数据。
-
Skipper 的路由规则可以在不停机的情况下更新。正如它的作者所述,Skipper 可以很好地与其他解决方案一起使用,比如 AWS ELB。
二、nginx ingress controller
2.1 nginx ingress controller位置
- 参考链接:https://www.nginx.com/products/nginx/kubernetes-ingress-controller
2.2 nginx ingress controller部署
- 项目地址:https://github.com/kubernetes/ingress-nginx
2.2.1 下载并修改配置文件
[root@k8s-master1 ~]# curl -k https://raw.githubusercontent.com/kubernetes/ingress-nginx/main/deploy/static/provider/baremetal/deploy.yaml -o deploy.yaml
[root@k8s-master1 ~]# ls
deploy.yaml
[root@k8s-master1 ~]# vim deploy.yaml
......
323 spec:
324 ports:
325 - appProtocol: http
326 name: http
327 port: 80
328 protocol: TCP
329 targetPort: http
330 - appProtocol: https
331 name: https
332 port: 443
333 protocol: TCP
334 targetPort: https
335 selector:
336 app.kubernetes.io/component: controller
337 app.kubernetes.io/instance: ingress-nginx
338 app.kubernetes.io/name: ingress-nginx
339 type: NodePort
把339行修改为LoadBalancer
323 spec:
324 ports:
325 - appProtocol: http
326 name: http
327 port: 80
328 protocol: TCP
329 targetPort: http
330 - appProtocol: https
331 name: https
332 port: 443
333 protocol: TCP
334 targetPort: https
335 selector:
336 app.kubernetes.io/component: controller
337 app.kubernetes.io/instance: ingress-nginx
338 app.kubernetes.io/name: ingress-nginx
339 type: LoadBalancer
2.2.2 应用资源清单文件
[root@k8s-master1 ~]# kubectl apply -f deploy.yaml
namespace/ingress-nginx created
serviceaccount/ingress-nginx created
serviceaccount/ingress-nginx-admission created
role.rbac.authorization.k8s.io/ingress-nginx created
role.rbac.authorization.k8s.io/ingress-nginx-admission created
clusterrole.rbac.authorization.k8s.io/ingress-nginx created
clusterrole.rbac.authorization.k8s.io/ingress-nginx-admission created
rolebinding.rbac.authorization.k8s.io/ingress-nginx created
rolebinding.rbac.authorization.k8s.io/ingress-nginx-admission created
clusterrolebinding.rbac.authorization.k8s.io/ingress-nginx created
clusterrolebinding.rbac.authorization.k8s.io/ingress-nginx-admission created
configmap/ingress-nginx-controller created
service/ingress-nginx-controller created
service/ingress-nginx-controller-admission created
deployment.apps/ingress-nginx-controller created
job.batch/ingress-nginx-admission-create created
job.batch/ingress-nginx-admission-patch created
ingressclass.networking.k8s.io/nginx created
validatingwebhookconfiguration.admissionregistration.k8s.io/ingress-nginx-admission created
2.2.3 验证部署结果
注意镜像较大,可提前下载至集群node节点
[root@k8s-master1 ~]# kubectl get pods -n ingress-nginx
NAME READY STATUS RESTARTS AGE
ingress-nginx-admission-create-xdpgp 0/1 Completed 0 91s
ingress-nginx-admission-patch-lgnxs 0/1 Completed 1 91s
ingress-nginx-controller-9596689c-j9p9l 1/1 Running 0 91s
[root@k8s-master1 ng]# kubectl get all -n ingress-nginx
NAME READY STATUS RESTARTS AGE
pod/ingress-nginx-admission-create-xdpgp 0/1 Completed 0 3m24s
pod/ingress-nginx-admission-patch-lgnxs 0/1 Completed 1 3m24s
pod/ingress-nginx-controller-9596689c-j9p9l 1/1 Running 0 3m24s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/ingress-nginx-controller LoadBalancer 10.96.183.188 192.168.10.91 80:32369/TCP,443:31775/TCP 3m25s
service/ingress-nginx-controller-admission ClusterIP 10.96.212.14 <none> 443/TCP 3m25s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/ingress-nginx-controller 1/1 1 1 3m24s
NAME DESIRED CURRENT READY AGE
replicaset.apps/ingress-nginx-controller-9596689c 1 1 1 3m24s
NAME COMPLETIONS DURATION AGE
job.batch/ingress-nginx-admission-create 1/1 2s 3m24s
job.batch/ingress-nginx-admission-patch 1/1 3s 3m24s
2.3 ingress对象应用案例
2.3 1 ingress-http案例
基于名称的负载均衡
2.3.1.1 创建deployment控制器类型应用
[root@k8s-master1 ~]# vim nginx.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx
namespace: ingress-nginx
spec:
replicas: 2
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: c1
image: nginx:1.15-alpine
imagePullPolicy: IfNotPresent
应用YAML
[root@k8s-master1 ~]# kubectl apply -f nginx.yml
deployment.extensions/nginx created
验证pod
[root@k8s-master1 ~]# kubectl get pods -n ingress-nginx
NAME READY STATUS RESTARTS AGE
nginx-79654d7b8-nhxpm 1/1 Running 0 12s
nginx-79654d7b8-tp8wg 1/1 Running 0 13s
nginx-ingress-controller-77db54fc46-kwwkt 1/1 Running 0 11m
2.3.1.2 创建service
[root@k8s-master1 ~]# vim nginx-service.yml
apiVersion: v1
kind: Service
metadata:
name: nginx-service
namespace: ingress-nginx
labels:
app: nginx
spec:
ports:
- port: 80
targetPort: 80
selector:
app: nginx
应用YAML
[root@k8s-master1 ~]# kubectl apply -f nginx-service.yml
service/nginx-service created
验证service
[root@k8s-master1 ~]# kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx-service ClusterIP 10.2.115.144 <none> 80/TCP 5s
2.3.1.3 创建ingress对象
[root@k8s-master1 ~]# vim ingress-nginx.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress-nginx #自定义ingress名称
namespace: ingress-nginx
annotations:
ingressclass.kubernetes.io/is-default-class: "true"
kubernetes.io/ingress.class: nginx
spec:
rules:
- host: www.kubemsb.com # 自定义域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-service # 对应上面创建的service名称
port:
number: 80
应用YAML
[root@k8s-master1 ~]# kubectl apply -f ingress-nginx.yaml
ingress.extensions/ingress-nginx created
验证ingress
[root@k8s-master1 ~]# kubectl get ingress -n ingress-nginx
NAME CLASS HOSTS ADDRESS PORTS AGE
ingress-nginx <none> www.kubemsb.com 192.168.10.12 80 113s
描述查看ingress信息
[root@k8s-master1 ~]# kubectl describe ingress ingress-nginx -n ingress-nginx
Name: ingress-nginx
Namespace: ingress-nginx
Address: 192.168.10.12
Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)
Rules:
Host Path Backends
---- ---- --------
www.kubemsb.com
/ nginx-service:80 (10.244.159.160:80,10.244.194.110:80)
Annotations: kubernetes.io/ingress.class: nginx
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Sync 2m (x2 over 2m56s) nginx-ingress-controller Scheduled for sync
[root@k8s-master1 ~]# kubectl get pods -o wide -n ingress-nginx
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-646d5c7b67-mpw9r 1/1 Running 0 4m15s 10.244.194.110 k8s-worker1 <none> <none>
nginx-646d5c7b67-v99gz 1/1 Running 0 4m15s 10.244.159.160 k8s-master1 <none> <none>
可以看到两个pod的IP正好对应ingress域名对应的IP
确认nginx-ingress-controller
的podIP为192.168.10.91
2.3.1.4 模拟客户端访问
1, 确认nginx-ingress-controller
的podIP, 下面命令查询的结果为192.168.10.91
[root@k8s-master1 ~]# kubectl get svc -n ingress-nginx |grep ingress
ingress-nginx-controller LoadBalancer 10.96.183.188 192.168.10.91 80:32369/TCP,443:31775/TCP 11m
ingress-nginx-controller-admission ClusterIP 10.96.212.14 <none> 443/TCP 11m
2, 在集群之外任一主机中添加上述域名与IP地址解析(模拟公网DNS)
[root@otherhost ~]# vim /etc/hosts
192.168.10.91 www.kubemsb.com
3, 准备pod内容器运行的web主页
[root@k8s-master1 ~]# kubectl get pods -n ingress-nginx
nginx-646d5c7b67-mpw9r 1/1 Running 0 8m34s
nginx-646d5c7b67-v99gz 1/1 Running 0 8m34s
[root@k8s-master1 ~]# kubectl exec -it nginx-646d5c7b67-mpw9r -n ingress-nginx -- /bin/sh
/ # echo "ingress web1" > /usr/share/nginx/html/index.html
/ # exit
[root@k8s-master1 ~]# kubectl exec -it nginx-646d5c7b67-v99gz -n ingress-nginx -- /bin/sh
/ # echo "ingress web2" > /usr/share/nginx/html/index.html
/ # exit
4, 访问及结果展示
[root@otherhost ~]# curl www.kubemsb.com
ingress web1
[root@otherhost ~]# curl www.kubemsb.com
ingress web2
2.3.2 ingress-http案例扩展
基于URI的负载均衡
2.3.2.1 创建第一个应用
[root@k8s-master1 ~]# vim nginx-uri-1.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-uri-1
namespace: ingress-nginx
spec:
replicas: 2
selector:
matchLabels:
app: nginx-uri-1
template:
metadata:
labels:
app: nginx-uri-1
spec:
containers:
- name: c1
image: nginx:1.15-alpine
imagePullPolicy: IfNotPresent
[root@k8s-master1 ~]# vim nginx-service-uri-1.yml
apiVersion: v1
kind: Service
metadata:
name: nginx-service-uri-1
namespace: ingress-nginx
labels:
app: nginx-uri-1
spec:
ports:
- port: 80
targetPort: 80
selector:
app: nginx-uri-1
# kubectl apply -f nginx-uri-1.yaml
# kubectl apply -f nginx-service-uri-1.yaml
2.3.2.2 创建第二个应用
[root@k8s-master1 ~]# vim nginx-uri-2.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-uri-2
namespace: ingress-nginx
spec:
replicas: 2
selector:
matchLabels:
app: nginx-uri-2
template:
metadata:
labels:
app: nginx-uri-2
spec:
containers:
- name: c1
image: nginx:1.15-alpine
imagePullPolicy: IfNotPresent
[root@k8s-master1 ~]# vim nginx-service-uri-2.yml
apiVersion: v1
kind: Service
metadata:
name: nginx-service-uri-2
namespace: ingress-nginx
labels:
app: nginx-uri-2
spec:
ports:
- port: 80
targetPort: 80
selector:
app: nginx-uri-2
# kubectl apply -f nginx-uri-2.yaml
# kubectl apply -f nginx-service-uri-2.yaml
# kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx-service-uri-1 ClusterIP 10.96.171.135 <none> 80/TCP 7m24s
nginx-service-uri-2 ClusterIP 10.96.234.164 <none> 80/TCP 4m11s
2.3.2.3 创建ingress对象
[root@k8s-master1 ~]# vim ingress-nginx.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress-uri
namespace: ingress-nginx
annotations:
ingressclass.kubernetes.io/is-default-class: "true"
kubernetes.io/ingress.class: nginx
spec:
rules:
- host: www.kubemsburi.com
http:
paths:
- path: /svc1
pathType: Prefix
backend:
service:
name: nginx-service-uri-1
port:
number: 80
- path: /svc2
pathType: Prefix
backend:
service:
name: nginx-service-uri-2
port:
number: 80
应用YAML
[root@master1 ~]# kubectl apply -f ingress-nginx-uri.yaml
ingress.networking.k8s.io/ingress-uri created
验证ingress
[root@master1 ~]# kubectl get ingress -n ingress-nginx
NAME CLASS HOSTS ADDRESS PORTS AGE
ingress-uri <none> www.kubemsburi.com 80 13s
描述查看ingress信息
[root@master1 ~]# kubectl describe ingress ingress-uri -n ingress-nginx
Name: ingress-uri
Namespace: ingress-nginx
Address: 192.168.10.12
Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)
Rules:
Host Path Backends
---- ---- --------
www.kubemsburi.com
/svc1 nginx-service-uri-1:80 (10.244.159.158:80,10.244.194.111:80)
/svc2 nginx-service-uri-2:80 (10.244.159.159:80,10.244.194.112:80)
Annotations: kubernetes.io/ingress.class: nginx
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Sync 4s (x2 over 32s) nginx-ingress-controller Scheduled for sync
[root@k8s-master1 ~]# kubectl get pods -o wide -n ingress-nginx
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-uri-1-7d7d75f86-dws96 1/1 Running 0 14m 10.244.159.158 k8s-master1 <none> <none>
nginx-uri-1-7d7d75f86-s8js4 1/1 Running 0 14m 10.244.194.111 k8s-worker1 <none> <none>
nginx-uri-2-7cdf7f89b7-8s4mg 1/1 Running 0 10m 10.244.194.112 k8s-worker1 <none> <none>
nginx-uri-2-7cdf7f89b7-gj8x6 1/1 Running 0 10m 10.244.159.159 k8s-master1 <none> <none>
确认nginx-ingress-controller
的podIP为192.168.10.91
2.3.1.4 模拟客户端访问
1, 确认nginx-ingress-controller
的podIP, 下面命令查询的结果为192.168.10.91
[root@k8s-master1 ~]# kubectl get svc -n ingress-nginx |grep ingress
ingress-nginx-controller LoadBalancer 10.96.183.188 192.168.10.91 80:32369/TCP,443:31775/TCP 11m
ingress-nginx-controller-admission ClusterIP 10.96.212.14 <none> 443/TCP 11m
2, 在集群之外任一主机中添加上述域名与IP地址解析(模拟公网DNS)
[root@otherhost ~]# vim /etc/hosts
192.168.10.91 www.kubemsburi.com
3, 准备pod内容器运行的web主页
[root@k8s-master1 ~]# kubectl exec -it nginx-uri-1-7d7d75f86-dws96 -n ingress-nginx -- /bin/sh
/ # mkdir /usr/share/nginx/html/svc1
/ # echo "sssvc1" > /usr/share/nginx/html/svc1/index.html
/ # exit
[root@k8s-master1 ~]# kubectl exec -it nginx-uri-1-7d7d75f86-s8js4 -n ingress-nginx -- /bin/sh
/ # mkdir /usr/share/nginx/html/svc1
/ # echo "sssvc1" > /usr/share/nginx/html/svc1/index.html
/ # exit
[root@k8s-master1 ~]# kubectl exec -it nginx-uri-2-7cdf7f89b7-8s4mg -n ingress-nginx -- /bin/sh
/ # mkdir /usr/share/nginx/html/svc2
/ # echo "sssvc2" > /usr/share/nginx/html/svc1/index.html
/ # exit
[root@k8s-master1 ~]# kubectl exec -it nginx-uri-2-7cdf7f89b7-gj8x6 -n ingress-nginx -- /bin/sh
/ # mkdir /usr/share/nginx/html/svc2
/ # echo "sssvc2" > /usr/share/nginx/html/svc1/index.html
/ # exit
4, 访问及结果展示
[root@otherhost ~]# curl www.kubemsburi.com/svc1/index.html
sssvc1
[root@otherhost ~]# curl www.kubemsburi.com/svc2/index.html
sssvc2
2.3.3 ingress-https案例
2.3.3.1 创建自签证书
[root@k8s-master1 ~]# mkdir ingress-https
[root@k8s-master1 ~]# cd ingress-https/
[root@k8s-master1 ingress-https]# openssl genrsa -out nginx.key 2048
[root@k8s-master1 ingress-https]# openssl req -new -x509 -key nginx.key -out nginx.pem -days 365
......
......
Country Name (2 letter code) [XX]:CN
State or Province Name (full name) []:GD
Locality Name (eg, city) [Default City]:SZ
Organization Name (eg, company) [Default Company Ltd]:IT
Organizational Unit Name (eg, section) []:it
Common Name (eg, your name or your server's hostname) []:kubemsbhost
Email Address []:admin@kubemsbhost.com
[root@k8s-master1 ingress-https]# ls
nginx.key nginx.pem
2.3.3.2 将证书创建成secret
[root@k8s-master1 ingress-https]# kubectl create secret tls nginx-tls-secret --cert=nginx.pem --key=nginx.key -n ingress-nginx
secret/nginx-tls-secret created
[root@k8s-master1 ingress-https]# kubectl get secrets -n ingress-nginx |grep nginx-tls-secret
nginx-tls-secret kubernetes.io/tls 2 38s
2.3.3.3 编排YAML并创建
[root@k8s-master1 ingress-https]# vim ingress-https.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx2
namespace: ingress-nginx
spec:
replicas: 2
selector:
matchLabels:
app: nginx2
template:
metadata:
labels:
app: nginx2
spec:
containers:
- name: c1
image: nginx:1.15-alpine
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 80
- name: https
containerPort: 443
---
apiVersion: v1
kind: Service
metadata:
name: nginx-service2
namespace: ingress-nginx
labels:
app: nginx2
spec:
ports:
- name: http
port: 80
targetPort: 80
- name: https
port: 443
targetPort: 443
selector:
app: nginx2
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress-nginx2
namespace: ingress-nginx
annotations:
ingressclass.kubernetes.io/is-default-class: "true"
kubernetes.io/ingress.class: nginx
spec:
tls:
- hosts:
- www.kubemsbhost.com # 域名
secretName: nginx-tls-secret # 调用前面创建的secret
rules:
- host: www.kubemsbhost.com # 域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-service2 # 对应服务名
port:
number: 80
[root@k8s-master1 ingress-https]# kubectl apply -f ingress-https.yml
deployment.apps/nginx2 created
service/nginx-service2 created
ingress.extensions/ingress-nginx2 created
验证
[root@k8s-master1 ~]# kubectl get ingress -n ingress-nginx
NAME CLASS HOSTS ADDRESS PORTS AGE
ingress-nginx2 <none> www.kubemsbhost.com 192.168.10.12 80, 443 2m14s
2.3.3.4 模拟客户端访问
[root@otherhost ~]# vim /etc/hosts
192.168.10.91 www.kubemsbhost.com 添加这行模拟DNS
[root@otherhost ~]# firefox https://www.kubemsbhost.com &
[1] 10892
关于可信任证书的说明:
如果需要在互联网中访问kubernetes集群中的服务是可信的,建议使用互联网中申请的SSL证书。
2.3.4 ingress+nodeport服务
[root@k8s-master1 ~]# vim ingress-nodeport.yml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx3
namespace: ingress-nginx
spec:
replicas: 2
selector:
matchLabels:
app: nginx3
template:
metadata:
labels:
app: nginx3
spec:
containers:
- name: c1
image: nginx:1.15-alpine
imagePullPolicy: IfNotPresent
---
apiVersion: v1
kind: Service
metadata:
name: nginx-service3
namespace: ingress-nginx
labels:
app: nginx3
spec:
type: NodePort # NodePort类型服务
ports:
- port: 80
targetPort: 80
selector:
app: nginx3
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress-nginx3
namespace: ingress-nginx
annotations:
ingressclass.kubernetes.io/is-default-class: "true"
kubernetes.io/ingress.class: nginx
spec:
rules:
- host: www.kubemsb3.com # 域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-service3 # 对应服务名
port:
number: 80
[root@k8s-master1 ~]# kubectl apply -f ingress-nodeport.yml
root@k8s-master1 ~]# kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx-service ClusterIP 10.2.115.144 <none> 80/TCP 22h
nginx-service2 ClusterIP 10.2.237.70 <none> 80/TCP,443/TCP 22h
nginx-service3 NodePort 10.2.75.250 <none> 80:26765/TCP 3m51s
nginx-service3是nodeport类型
[root@otherhost ~]# vim /etc/hosts
192.168.10.91 www.kubemsb3.com 添加这行模拟DNS
[root@otherhost ~]# curl www.kubemsb3.com
基于Ingress Nginx实现灰度发布系统
工作中,我们会经常对应用进行升级发版,在互联网公司尤为频繁,主要是为了满足业务的快速发展。我们经常用到的发布方式有滚动更新、蓝绿发布、灰度发布。
- 滚动更新:依次进行新旧替换,直到旧的全部被替换为止。
- 蓝绿发布:两套独立的系统,对外提供服务的称为绿系统,待上线的服务称为蓝系统,当蓝系统里面的应用测试完成后,用户流量接入蓝系统,蓝系统将称为绿系统,以前的绿系统就可以销毁。
- 灰度发布:在一套集群中存在稳定和灰度两个版本,灰度版本可以限制只针对部分人员可用,待灰度版本测试完成后,可以将灰度版本升级为稳定版本,旧的稳定版本就可以下线了,我们也称之为金丝雀发布。
本次分享如何通过ingress-nginx controller实现灰度发布。
一、通过ingress-nginx实现灰度发布原理
ingress-nginx是Kubernetes官方推荐的ingress controller,它是基于nginx实现的,增加了一组用于实现额外功能的Lua插件。
为了实现灰度发布,ingress-nginx通过定义annotation来实现不同场景的灰度发布,其支持的规则如下:
- nginx.ingress.kubernetes.io/canary-by-header:基于 Request Header 的流量切分,适用于灰度发布以及 A/B 测试。当 Request Header 设置为 always时,请求将会被一直发送到 Canary 版本;当 Request Header 设置为 never时,请求不会被发送到 Canary 入口;对于任何其他 Header 值,将忽略 Header,并通过优先级将请求与其他金丝雀规则进行优先级的比较。
- nginx.ingress.kubernetes.io/canary-by-header-value:要匹配的 Request Header 的值,用于通知 Ingress 将请求路由到 Canary Ingress 中指定的服务。当 Request Header 设置为此值时,它将被路由到 Canary 入口。该规则允许用户自定义 Request Header 的值,必须与上一个 annotation (即:canary-by-header)一起使用。
- nginx.ingress.kubernetes.io/canary-weight:基于服务权重的流量切分,适用于蓝绿部署,权重范围 0 - 100 按百分比将请求路由到 Canary Ingress 中指定的服务。权重为 0 意味着该金丝雀规则不会向 Canary 入口的服务发送任何请求。权重为 100 意味着所有请求都将被发送到 Canary 入口。
- nginx.ingress.kubernetes.io/canary-by-cookie:基于 Cookie 的流量切分,适用于灰度发布与 A/B 测试。用于通知 Ingress 将请求路由到 Canary Ingress 中指定的服务的cookie。当 cookie 值设置为 always时,它将被路由到 Canary 入口;当 cookie 值设置为 never时,请求不会被发送到 Canary 入口;对于任何其他值,将忽略 cookie 并将请求与其他金丝雀规则进行优先级的比较。
以上规则优先顺序为:
canary-by-header -> canary-by-cookie -> canary-weight
二、通过ingress-nginx实现灰度发布场景
2.1 基于服务权重的流量切分
假如在生产上已经运行了A应用对外提供服务,此时开发修复了一些Bug,需要发布A1版本将其上线,但是我们又不希望直接的将所有流量接入到新的A1版本,而是希望将10%的流量进入到A1中,待A1稳定后,才会将所有流量接入进来,再下线原来的A版本。
实现方法:
在canary ingress中添加如下annotation
nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-by-header: "Region"
nginx.ingress.kubernetes.io/canary-by-header-value: "shenzhen"
其中:
nginx.ingress.kubernetes.io/canary: “true” 开启canary
nginx.ingress.kubernetes.io/canary-by-header: “Region” 指定header关键字
nginx.ingress.kubernetes.io/canary-by-header-value: “shenzhen” 指定header关键字对应的value
三、通过ingress-nginx实现灰度发布实现思路
1、在K8S集群中运行2个应用版本,一个是stable版本,一个是canary版本
2、定义stable版本ingress,提供运行的应用正常访问;定义canary版本,在metadata中添加annotation实现类度发布,例如根据流量百分比或用户请求header
3、经过一定时间的运行,canary版本可正常提供服务后,将其切换为stable版本,并将原stable版本下线即可
四、通过ingress-nginx实现灰度发布系统
4.1 负载均衡器metallb部署
4.1.1 kube-proxy代理模式修改
[root@k8s-master01 ~]# kubectl get configmap -n kube-system
NAME DATA AGE
......
kube-proxy 2 35h
[root@k8s-master01 ~]# kubectl edit configmap kube-proxy -n kube-system
ipvs:
excludeCIDRs: null
minSyncPeriod: 0s
scheduler: ""
strictARP: true 由原来的flase修改为true
syncPeriod: 0s
tcpFinTimeout: 0s
tcpTimeout: 0s
udpTimeout: 0s
kind: KubeProxyConfiguration
logging:
flushFrequency: 0
options:
json:
infoBufferSize: "0"
verbosity: 0
metricsBindAddress: ""
mode: "ipvs" 默认为空,添加ipvs
[root@k8s-master01 ~]# kubectl rollout restart daemonset kube-proxy -n kube-system
4.1.2 metallb部署
4.1.2.1 metallb部署
[root@k8s-master01 ~]# kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.13.11/config/manifests/metallb-native.yaml
4.1.2.2 IP地址池准备
[root@k8s-master01 ~]# vim ippool.yaml
[root@k8s-master01 ~]# cat ippool.yaml
apiVersion: metallb.io/v1beta1
kind: IPAddressPool
metadata:
name: first-pool
namespace: metallb-system
spec:
addresses:
- 192.168.10.240-192.168.10.250
[root@k8s-master01 ~]# kubectl apply -f ippool.yaml
4.1.2.3 开启二层通告
[root@k8s-master01 ~]# vim l2.yaml
[root@k8s-master01 ~]# cat l2.yaml
apiVersion: metallb.io/v1beta1
kind: L2Advertisement
metadata:
name: example
namespace: metallb-system
[root@k8s-master01 ~]# kubectl apply -f l2.yaml
4.2 ingress nginx部署
4.2.1 获取ingress nginx部署文件
[root@k8s-master01 ~]# wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.8.2/deploy/static/provider/cloud/deploy.yaml
4.2.2 修改ingress nginx部署文件
[root@k8s-master01 ~]# vim deploy.yaml
[root@k8s-master01 ~]# cat deploy.yaml
......
---
apiVersion: v1
kind: Service
metadata:
labels:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.8.2
name: ingress-nginx-controller
namespace: ingress-nginx
spec:
externalTrafficPolicy: Cluster 由Local修改为Cluster
ipFamilies:
- IPv4
ipFamilyPolicy: SingleStack
ports:
- appProtocol: http
name: http
port: 80
protocol: TCP
targetPort: http
- appProtocol: https
name: https
port: 443
protocol: TCP
targetPort: https
selector:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
type: LoadBalancer 此处为LoadBalancer
......
4.2.3 部署ingress nginx
[root@k8s-master01 ~]# kubectl apply -f deploy.yaml
[root@k8s-master01 ~]# kubectl get ns
NAME STATUS AGE
......
ingress-nginx Active 10h
[root@k8s-master01 ~]# kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
ingress-nginx-controller LoadBalancer 10.111.3.227 192.168.10.240 80:32757/TCP,443:31886/TCP 10h
ingress-nginx-controller-admission ClusterIP 10.106.142.161 <none> 443/TCP 10h
有必要修改configmap,操作如下:
[root@k8s-master01 ~]# kubectl get configmap -n ingress-nginx
NAME DATA AGE
ingress-nginx-controller 2 12h
[root@k8s-master01 ~]# kubectl edit configmap ingress-nginx-controller -n ingress-nginx
apiVersion: v1
data:
allow-snippet-annotations: "true"
enable-canary: "true"
[root@k8s-master01 ~]# kubectl get deployment -n ingress-nginx
NAME READY UP-TO-DATE AVAILABLE AGE
ingress-nginx-controller 1/1 1 1 12h
[root@k8s-master01 ~]# kubectl rollout restart deployment ingress-nginx-controller -n ingress-nginx
4.3 应用服务部署
4.3.1 v1版本部署
[root@k8s-master01 ~]# vim 01-deploy-nginx-v1.yaml
[root@k8s-master01 ~]# cat 01-deploy-nginx-v1.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-v1
spec:
replicas: 1
selector:
matchLabels:
app: nginx
version: v1
template:
metadata:
labels:
app: nginx
version: v1
spec:
containers:
- name: nginx
image: "openresty/openresty:centos"
ports:
- name: http
protocol: TCP
containerPort: 80
volumeMounts:
- mountPath: /usr/local/openresty/nginx/conf/nginx.conf
name: config
subPath: nginx.conf
volumes:
- name: config
configMap:
name: nginx-v1
---
apiVersion: v1
kind: ConfigMap
metadata:
labels:
app: nginx
version: v1
name: nginx-v1
data:
nginx.conf: |-
worker_processes 1;
events {
accept_mutex on;
multi_accept on;
use epoll;
worker_connections 1024;
}
http {
ignore_invalid_headers off;
server {
listen 80;
location / {
access_by_lua '
local header_str = ngx.say("nginx-v1")
';
}
}
}
---
apiVersion: v1
kind: Service
metadata:
name: nginx-v1
spec:
type: ClusterIP
ports:
- port: 80
protocol: TCP
name: http
selector:
app: nginx
version: v1
[root@k8s-master01 ~]# kubectl apply -f 01-deploy-nginx-v1.yaml
deployment.apps/nginx-v1 created
configmap/nginx-v1 created
service/nginx-v1 created
[root@k8s-master01 ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-v1-b94d7c84-vt62f 1/1 Running 0 2m19s
[root@k8s-master01 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 36h
nginx-v1 ClusterIP 10.101.173.87 <none> 80/TCP 2m48s
[root@k8s-master01 ~]# curl http://10.101.173.87
nginx-v1
4.3.2 v2版本部署
[root@k8s-master01 ~]# vim 02-deploy-nginx-v2.yaml
[root@k8s-master01 ~]# cat 02-deploy-nginx-v2.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-v2
spec:
replicas: 1
selector:
matchLabels:
app: nginx
version: v2
template:
metadata:
labels:
app: nginx
version: v2
spec:
containers:
- name: nginx
image: "openresty/openresty:centos"
ports:
- name: http
protocol: TCP
containerPort: 80
volumeMounts:
- mountPath: /usr/local/openresty/nginx/conf/nginx.conf
name: config
subPath: nginx.conf
volumes:
- name: config
configMap:
name: nginx-v2
---
apiVersion: v1
kind: ConfigMap
metadata:
labels:
app: nginx
version: v2
name: nginx-v2
data:
nginx.conf: |-
worker_processes 1;
events {
accept_mutex on;
multi_accept on;
use epoll;
worker_connections 1024;
}
http {
ignore_invalid_headers off;
server {
listen 80;
location / {
access_by_lua '
local header_str = ngx.say("nginx-v2")
';
}
}
}
---
apiVersion: v1
kind: Service
metadata:
name: nginx-v2
spec:
type: ClusterIP
ports:
- port: 80
protocol: TCP
name: http
selector:
app: nginx
version: v2
[root@k8s-master01 ~]# kubectl apply -f 02-deploy-nginx-v2.yaml
deployment.apps/nginx-v2 created
configmap/nginx-v2 created
service/nginx-v2 created
[root@k8s-master01 ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
......
nginx-v2-567b457d6-f6d5r 1/1 Running 0 36s
[root@k8s-master01 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 36h
nginx-v1 ClusterIP 10.101.173.87 <none> 80/TCP 7m10s
nginx-v2 ClusterIP 10.106.237.15 <none> 80/TCP 70s
[root@k8s-master01 ~]# curl http://10.106.237.15
nginx-v2
4.4 创建stable版本ingress资源对象
[root@k8s-master01 ~]# vim 03-stable-ingress.yaml
[root@k8s-master01 ~]# cat 03-stable-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: nginx-v1 #自定义ingress名称
namespace: default
spec:
ingressClassName: nginx
rules:
- host: www.kubemsb.com # 自定义域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-v1 # 对应上面创建的service名称
port:
number: 80
[root@k8s-master01 ~]# kubectl apply -f 03-stable-ingress.yaml
[root@k8s-master01 ~]# kubectl get ingress
NAME CLASS HOSTS ADDRESS PORTS AGE
nginx-v1 nginx www.kubemsb.com 192.168.10.240 80 58s
[root@k8s-master01 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.10.140 k8s-master01
192.168.10.141 k8s-worker01
192.168.10.142 k8s-worker02
192.168.10.240 www.kubemsb.com
[root@k8s-master01 ~]# curl http://www.kubemsb.com
nginx-v1
4.5 流量切分
4.5.1 基于服务权重的流量切分
[root@k8s-master01 ~]# vim 04-canary-ingress-weight.yaml
[root@k8s-master01 ~]# cat 04-canary-ingress-weight.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: nginx-v2 #自定义ingress名称
namespace: default
annotations:
nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-weight: "10"
spec:
ingressClassName: nginx
rules:
- host: www.kubemsb.com # 自定义域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-v2 # 对应上面创建的service名称
port:
number: 80
[root@k8s-master01 ~]# kubectl apply -f 04-canary-ingress-weight.yaml
[root@k8s-master01 ~]# kubectl get ingress
NAME CLASS HOSTS ADDRESS PORTS AGE
nginx-v1 nginx www.kubemsb.com 192.168.10.240 80 15m
nginx-v2 nginx www.kubemsb.com 80 5s
[root@k8s-master01 ~]# for i in {1..10};do curl http://www.kubemsb.com;done
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v1
nginx-v2
4.5.2 基于用户请求头Header的流量切分
[root@k8s-master01 ~]# vim 05-canary-ingress-header.yaml
[root@k8s-master01 ~]# cat 05-canary-ingress-header.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: nginx-v2 #自定义ingress名称
namespace: default
annotations:
nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-by-header: "Region"
nginx.ingress.kubernetes.io/canary-by-header-pattern: "shenzhen"
spec:
ingressClassName: nginx
rules:
- host: www.kubemsb.com # 自定义域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-v2 # 对应上面创建的service名称
port:
number: 80
[root@k8s-master01 ~]# kubectl apply -f 05-canary-ingress-header.yaml
[root@k8s-master01 ~]# kubectl get ingress
NAME CLASS HOSTS ADDRESS PORTS AGE
nginx-v1 nginx www.kubemsb.com 192.168.10.240 80 83m
nginx-v2 nginx www.kubemsb.com 80 7s
[root@k8s-master01 ~]# curl http://www.kubemsb.com
nginx-v1
[root@k8s-master01 ~]# curl -H "Region: beijing" http://www.kubemsb.com
nginx-v1
[root@k8s-master01 ~]# curl -H "Region: shanghai" http://www.kubemsb.com
nginx-v1
[root@k8s-master01 ~]# curl -H "Region: shenzhen" http://www.kubemsb.com
nginx-v2
4.5.3 基于Cookie的流量切分
使用 Cookie 则无法自定义 value,以模拟灰度shenzhen地域用户为例,仅将带有名为
user_from_shenzhen
的 Cookie 的请求转发给当前 Canary Ingress
[root@k8s-master01 ~]# vim 06-canary-ingress-cookie.yaml
[root@k8s-master01 ~]# cat 06-canary-ingress-cookie.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: nginx-v2 #自定义ingress名称
namespace: default
annotations:
nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-by-cookie: "user_from_shenzhen"
spec:
ingressClassName: nginx
rules:
- host: www.kubemsb.com # 自定义域名
http:
paths:
- pathType: Prefix
path: "/"
backend:
service:
name: nginx-v2 # 对应上面创建的service名称
port:
number: 80
[root@k8s-master01 ~]# kubectl apply -f 06-canary-ingress-cookie.yaml
[root@k8s-master01 ~]# kubectl get ingress
NAME CLASS HOSTS ADDRESS PORTS AGE
nginx-v1 nginx www.kubemsb.com 192.168.10.240 80 98m
nginx-v2 nginx www.kubemsb.com 80 4s
[root@k8s-master01 ~]# curl --cookie "user_from_beijing" http://www.kubemsb.com
nginx-v1
[root@k8s-master01 ~]# curl --cookie "user_from_shenzhen" http://www.kubemsb.com
nginx-v1
[root@k8s-master01 ~]# curl --cookie "user_from_shenzhen=always" http://www.kubemsb.com
nginx-v2
可查看当仅有 cookie
user_from_shenzhen
为always
的请求才由 v2 版本的服务响应。