Service介绍
在kubernetes中,pod是应用程序的载体,我们可以通过pod的ip来访问应用程序,但是pod的ip地址不是固定的,这也就意味着不方便直接采用pod的ip对服务进行访问。
为了解决这个问题,kubernetes提供了Service资源,Service会对提供同一个服务的多个pod进行聚合,并且提供一个统一的入口地址。通过访问Service的入口地址就能访问到后面的pod服务
Kubernetes Service定义了这样一种抽象:逻辑上的一组Pod,一种可以访问它们的策略 —— 通常被称为微服务。这一组Pod能够被Service访问到,通常是通过selector实现的。
举个例子,考虑一个图片处理后端,它运行了3个副本。这些副本是可互换的——前端不需要关心它们调用了哪个后端副本。然而组成这一组后端程序的Pod实际上可能会发生变化,前端客户端不应该也没必要知道,而且也不需要跟踪这一组后端的状态。Service定义的抽象能够解耦这种关联。
Service可以提供负载均衡的能力,但是使用上存在如下限制:
只能提供4层负载均衡能力,而没有7层功能。有时我们可能需要更多的匹配规则来转发请求,这点上4层负载均衡是不支持的
如web访问的service服务示例图
VIP和Service代理
在 Kubernetes 集群中,每个 Node 运行一个 kube-proxy 进程。kube-proxy 负责为 Service 实现了一种 VIP(虚拟 IP)的形式,而不是 ExternalName 的形式。
从Kubernetes v1.0开始,已经可以使用 userspace代理模式。Kubernetes v1.1添加了 iptables 代理模式,在 Kubernetes v1.2 中kube-proxy 的 iptables 模式成为默认设置。Kubernetes v1.8添加了 ipvs 代理模式。
为什么不使用 DNS 轮询?
原因如下:
- DNS 实现的历史由来已久,它不遵守记录 TTL,并且在名称查找到结果后会对其进行缓存。
- 有些应用程序仅执行一次 DNS 查找,并无限期地缓存结果。
- 即使应用和库进行了适当的重新解析,DNS 记录上的 TTL 值低或为零也可能会给 DNS 带来高负载,从而使管理变得困难。
总之就是因为有缓存,因此不合适。
Service在很多情况下只是一个概念,真正起作用的其实是kube-proxy服务进程,每个Node节点上都运行着一个kube-proxy服务进程。当创建Service的时候会通过api-server向etcd写入创建的service的信息,而kube-proxy会基于监听的机制发现这种Service的变动,然后它会将最新的Service信息转换成对应的访问规则
# 192.168.170.138:80 是service提供的访问入口
# 当访问这个入口的时候,可以发现后面有三个pod的服务在等待调用,
# kube-proxy会基于rr(轮询)的策略,将请求分发到其中一个pod上去
# 这个规则会同时在集群内的所有节点上都生成,所以在任何一个节点上访问都可以。
[root@node1 ~]# ipvsadm -Ln
[root@node1 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.170.138:30318 rr
-> 10.244.1.6:80 Masq 1 0 0
TCP 10.96.0.1:443 rr
-> 192.168.170.135:6443 Masq 1 1 0
TCP 10.96.0.10:53 rr
-> 10.244.0.6:53 Masq 1 0 0
-> 10.244.0.7:53 Masq 1 0 0
kube-proxy目前支持三种工作模式:
userspace 模式
userspace模式下,kube-proxy会为每一个Service创建一个监听端口,发向Cluster IP的请求被Iptables规则重定向到kube-proxy监听的端口上,kube-proxy根据LB算法选择一个提供服务的Pod并和其建立链接,以将请求转发到Pod上。 该模式下,kube-proxy充当了一个四层负责均衡器的角色。由于kube-proxy运行在userspace中,在进行转发处理时会增加内核和用户空间之间的数据拷贝,虽然比较稳定,但是效率比较低
iptables 代理模式
这种模式,kube-proxy 会监视 Kubernetes 控制节点对 Service 对象和 Endpoints 对象的添加和移除。 对每个 Service,它会配置 iptables 规则,从而捕获到达该 Service 的 clusterIP 和端口的请求,进而将请求重定向到 Service 的一组 backend 中的某个上面。对于每个 Endpoints 对象,它也会配置 iptables 规则,这个规则会选择一个 backend 组合。
默认的策略是,kube-proxy 在 iptables 模式下随机选择一个 backend。
使用 iptables 处理流量具有较低的系统开销,因为流量由 Linux netfilter 处理,而无需在用户空间和内核空间之间切换。 这种方法也可能更可靠。
如果 kube-proxy 在 iptables模式下运行,并且所选的第一个 Pod 没有响应,则连接失败。 这与userspace模式不同:在这种情况下,kube-proxy 将检测到与第一个 Pod 的连接已失败,并会自动使用其他后端 Pod 重试。
我们可以使用 Pod readiness 探测器 验证后端 Pod 是否可以正常工作,以便 iptables 模式下的 kube-proxy 仅看到测试正常的后端。这样做意味着可以避免将流量通过 kube-proxy 发送到已知已失败的Pod
在 ipvs 模式下,kube-proxy监视Kubernetes服务(Service)和端点(Endpoints),调用 netlink 接口相应地创建 IPVS 规则, 并定期将 IPVS 规则与 Kubernetes服务(Service)和端点(Endpoints)同步。该控制循环可确保 IPVS 状态与所需状态匹配。访问服务(Service)时,IPVS 将流量定向到后端Pod之一。
IPVS代理模式基于类似于 iptables 模式的 netfilter 挂钩函数,但是使用哈希表作为基础数据结构,并且在内核空间中工作。 这意味着,与 iptables 模式下的 kube-proxy 相比,IPVS 模式下的 kube-proxy 重定向通信的延迟要短,并且在同步代理规则时具有更好的性能。与其他代理模式相比,IPVS 模式还支持更高的网络流量吞吐量。
IPVS提供了更多选项来平衡后端Pod的流量。这些是:
- rr: round-robin
- lc: least connection (smallest number of open connections)
- dh: destination hashing
- sh: source hashing
- sed: shortest expected delay
- nq: never queue
注意:要在 IPVS 模式下运行 kube-proxy,必须在启动 kube-proxy 之前使 IPVS Linux 在节点上可用。 当 kube-proxy 以 IPVS 代理模式启动时,它将验证 IPVS 内核模块是否可用。 如果未检测到 IPVS 内核模块,则 kube-proxy 将退回到以 iptables 代理模式运行
Service服务类型
Kubernetes 中Service有以下4中类型:
- ClusterIP:默认类型,自动分配一个仅Cluster内部可以访问的虚拟IP
- NodePort:通过每个 Node 上的 IP 和静态端口(NodePort)暴露服务。以ClusterIP为基础,NodePort 服务会路由到 ClusterIP 服务。通过请求 :,可以从集群的外部访问一个集群内部的 NodePort 服务。
- LoadBalancer:使用云提供商的负载均衡器,可以向外部暴露服务。外部的负载均衡器可以路由到 NodePort 服务和 ClusterIP 服务。
- ExternalName:通过返回 CNAME 和它的值,可以将服务映射到 externalName 字段的内容(例如,foo.bar.example.com)。没有任何类型代理被创建。
需要注意的是:Service 能够将一个接收 port 映射到任意的 targetPort。默认情况下,targetPort 将被设置为与 port 字段相同的值。
Service域名格式:$(service name).$(namespace).svc.cluster.local,其中 cluster.local 为指定的集群的域名
Deoployment的资源清单
[root@k8s-master mainfest]# vim deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: pc-deployment
namespace: dev
spec:
replicas: 3
selector:
matchLabels:
app: nginx-pod
template:
metadata:
labels:
app: nginx-pod
spec:
containers:
- name: nginx
image: nginx:1.17.1
ports:
- containerPort: 80
[root@k8s-master mainfest]# kubectl create -f deployment.yaml
deployment.apps/deploy created
# 查看pod详情
[root@k8s-master mainfest]# kubectl get pods -n dev -o wide --show-labels
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES LABELS
nginx 1/1 Running 1 7d11h 10.244.2.4 node2.example.com <none> <none> <none>
pc-deployment-5ffc5bf56c-4b776 1/1 Running 0 109s 10.244.2.7 node2.example.com <none> <none> app=nginx-pod,pod-template-hash=5ffc5bf56c
pc-deployment-5ffc5bf56c-ktnp8 1/1 Running 0 109s 10.244.2.8 node2.example.com <none> <none> app=nginx-pod,pod-template-hash=5ffc5bf56c
pc-deployment-5ffc5bf56c-vh4f9 1/1 Running 0 109s 10.244.1.9 node1.example.com <none> <none> app=nginx-pod,pod-template-hash=5ffc5bf56c
访问
[root@k8s-master mainfest]# curl 10.244.2.7
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
[root@master mainfest]# curl 10.244.2.8
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
[root@master mainfest]# curl 10.244.1.9
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
ClusterIP类型示例
创建cluster IP类型的service
[root@k8s-master mainfest]# vim svc-clusterip.yaml
apiVersion: v1
kind: Service
metadata:
name: svc-clusterip
spec:
type: ClusterIP //可以不写,默认为ClusterIP
selector:
app: nginx
ports:
- name: nginx
port: 80
targetPort: 80
[root@k8s-master mainfest]# kubectl apply -f svc-clusterip.yaml
service/svc-clusterip created
[root@k8s-master mainfest]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 6d23h
svc-clusterip ClusterIP 10.105.207.162 <none> 80/TCP 2m39s
访问
[root@k8s-master mainfest]# curl 10.105.207.162
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
NodePort类型示例
如果将 type 字段设置为 NodePort,则 Kubernetes 控制层面将在 --service-node-port-range 标志指定的范围内分配端口(默认值:30000-32767
[root@k8s-master mainfest]# vim svc-nodeport.yaml
apiVersion: v1
kind: Service
metadata:
name: service-clusterip
namespace: dev
spec:
selector:
app: nginx-pod
clusterIP: 10.97.97.97 # service的ip地址,如果不写,默认会生成一个
type: ClusterIP
ports:
- port: 80 # Service端口
targetPort: 80 # pod端口
# 创建service
[root@k8s-master mainfest]# kubectl create -f service-clusterip.yaml
service/service-clusterip created
# 查看service
[root@k8s-master mainfest]# kubectl get svc -n dev -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service-clusterip ClusterIP 10.97.97.97 <none> 80/TCP 6s app=nginx-pod
# 查看service的详细信息
# 在这里有一个Endpoints列表,里面就是当前service可以负载到的服务入口
[root@k8s-master mainfest]# kubectl describe svc service-clusterip -n dev
Name: service-clusterip
Namespace: dev
Labels: <none>
Annotations: <none>
Selector: app=nginx-pod
Type: ClusterIP
IP Families: <none>
IP: 10.97.97.97
IPs: 10.97.97.97
Port: <unset> 80/TCP
TargetPort: 80/TCP
Endpoints: 10.244.1.9:80,10.244.2.7:80,10.244.2.8:80
Session Affinity: None
Events: <none>
# 查看ipvs的映射规则
[root@k8s-master mainfest]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 172.17.0.1:30318 rr
-> 10.244.1.6:80 Masq 1 0 0
TCP 192.168.122.1:30318 rr
-> 10.244.1.6:80 Masq 1 0 0
# 访问172.17.0.1:30318观察效果
[root@k8s-master ~]# curl 172.17.0.1:30318
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
HeadLiness类型的Service
在某些场景中,开发人员可能不想使用Service提供的负载均衡功能,而希望自己来控制负载均衡策略,针对这种情况,kubernetes提供了HeadLiness Service,这类Service不会分配Cluster IP,如果想要访问service,只能通过service的域名进行查询。
创建service-headliness.yaml
[root@k8s-master mainfest]# vi service-headliness.yaml
apiVersion: v1
kind: Service
metadata:
name: service-headliness
namespace: dev
spec:
selector:
app: nginx-pod
clusterIP: None # 将clusterIP设置为None,即可创建headliness Service
type: ClusterIP
ports:
- port: 80
targetPort: 80
# 创建service
[root@k8s-master mainfest]# kubectl create -f service-headliness.yaml
service/service-headliness created
# 获取service, 发现CLUSTER-IP未分配
[root@k8s-master mainfest]# kubectl get svc service-headliness -n dev -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service-headliness ClusterIP None <none> 80/TCP 9s app=nginx-pod
# 查看service详情
[root@k8s-master mainfest]# kubectl describe svc service-headliness -n dev
Name: service-headliness
Namespace: dev
Labels: <none>
Annotations: <none>
Selector: app=nginx-pod
Type: ClusterIP
IP Families: <none>
IP: None
IPs: None
Port: <unset> 80/TCP
TargetPort: 80/TCP
Endpoints: <none>
Session Affinity: None
Events: <none>
LoadBalancer类型示例
在使用支持外部负载均衡器的云提供商的服务时,设置 type 的值为 "LoadBalancer", 将为 Service 提供负载均衡器。 负载均衡器是异步创建的,关于被提供的负载均衡器的信息将会通过 Service 的 status.loadBalancer 字段发布出去
apiVersion: v1
kind: Service
metadata:
name: my-service
spec:
selector:
app: MyApp
ports:
- protocol: TCP
port: 80
targetPort: 9376
clusterIP: 10.0.171.239
type: LoadBalancer
status:
loadBalancer:
ingress:
- ip: 192.0.2.127
来自外部负载均衡器的流量将直接重定向到后端 Pod 上,不过实际它们是如何工作的,这要依赖于云提供商。
某些云提供商允许设置 loadBalancerIP。 在这些情况下,将根据用户设置的 loadBalancerIP 来创建负载均衡器。 如果没有设置 loadBalancerIP 字段,将会给负载均衡器指派一个临时 IP。 如果设置了 loadBalancerIP,但云提供商并不支持这种特性,那么设置的 loadBalancerIP 值将会被忽略掉。
Ingress介绍
在前面课程中已经提到,Service对集群之外暴露服务的主要方式有两种:NotePort和LoadBalancer,但是这两种方式,都有一定的缺点:
NodePort方式的缺点是会占用很多集群机器的端口,那么当集群服务变多的时候,这个缺点就愈发明显
LB方式的缺点是每个service需要一个LB,浪费、麻烦,并且需要kubernetes之外设备的支持
基于这种现状,kubernetes提供了Ingress资源对象,Ingress只需要一个NodePort或者一个LB就可以满足暴露多个Service的需求。工作机制大致如下图表示
实际上,Ingress相当于一个7层的负载均衡器,是kubernetes对反向代理的一个抽象,它的工作原理类似于Nginx,可以理解成在Ingress里建立诸多映射规则,Ingress Controller通过监听这些配置规则并转化成Nginx的反向代理配置 , 然后对外部提供服务。在这里有两个核心概念:
- ingress:kubernetes中的一个对象,作用是定义请求如何转发到service的规则
- ingress controller:具体实现反向代理及负载均衡的程序,对ingress定义的规则进行解析,根据配置的规则来实现请求转发,实现方式有很多,比如Nginx, Contour, Haproxy等等
Ingress(以Nginx为例)的工作原理如下: - 用户编写Ingress规则,说明哪个域名对应kubernetes集群中的哪个Service
- Ingress控制器动态感知Ingress服务规则的变化,然后生成一段对应的Nginx反向代理配置
- Ingress控制器会将生成的Nginx配置写入到一个运行着的Nginx服务中,并动态更新
- 到此为止,其实真正在工作的就是一个Nginx了,内部配置了用户定义的请求转发规则
Ingress使用
环境准备
搭建ingress环境
# 创建文件夹
[root@k8s-master ~]# mkdir ingress-controller
[root@k8s-master ~]# cd ingress-controller
# 获取ingress-nginx,本次案例使用的是1.31版本
# 修改deploy.yaml文件中的仓库
# 修改quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.30.0
# 为dyrnq/ingress-nginx-controller:v1.3.1
[root@k8s-master ingress-controller]# grep image deploy.yaml
image: dyrnq/ingress-nginx-controller:v1.3.1
imagePullPolicy: IfNotPresent
image: dyrnq/kube-webhook-certgen:v1.3.0
imagePullPolicy: IfNotPresent
image: dyrnq/kube-webhook-certgen:v1.3.0
imagePullPolicy: IfNotPresent
[root@k8s-master ingress-controller]#
# 创建ingress-nginx
[root@k8s-master ingress-controller]# kubectl apply -f deploy.yaml
# 查看ingress-nginx
[root@k8s-master ~]# kubectl get pods -n ingress-nginx
NAME READY STATUS RESTARTS AGE
ingress-nginx-admission-create-zrp92 0/1 Completed 0 49s
ingress-nginx-admission-patch-s2fj5 0/1 Completed 0 49s
ingress-nginx-controller-5dbc974cb-frg8k 1/1 Running 0 49s
# 查看service
[root@k8s-master ingress-controller]# kubectl get svc -n ingress-nginxNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
ingress-nginx-controller NodePort 10.98.74.130 <none> 80:31313/TCP,443:32641/TCP 53s
ingress-nginx-controller-admission ClusterIP 10.99.61.209 <none> 443/TCP 53s
编写yaml文件
[root@k8s-master ~]# cat ingress-controller/deploy.yaml
apiVersion: v1
kind: Namespace
metadata:
labels:
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
name: ingress-nginx
---
apiVersion: v1
automountServiceAccountToken: true
kind: ServiceAccount
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: 1.3.1
name: ingress-nginx
namespace: ingress-nginx
---
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
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: 1.3.1
name: ingress-nginx
namespace: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- namespaces
verbs:
- get
- apiGroups:
- ""
resources:
- configmaps
- pods
- secrets
- endpoints
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- networking.k8s.io
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- networking.k8s.io
resources:
- ingresses/status
verbs:
- update
- apiGroups:
- networking.k8s.io
resources:
- ingressclasses
verbs:
- get
- list
- watch
- apiGroups:
- ""
resourceNames:
- ingress-controller-leader
resources:
- configmaps
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- coordination.k8s.io
resourceNames:
- ingress-controller-leader
resources:
- leases
verbs:
- get
- update
- apiGroups:
- coordination.k8s.io
resources:
- leases
verbs:
- create
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
namespace: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- secrets
verbs:
- get
- create
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
labels:
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
- namespaces
verbs:
- list
- watch
- apiGroups:
- coordination.k8s.io
resources:
- leases
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes
verbs:
- get
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- networking.k8s.io
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
- apiGroups:
- networking.k8s.io
resources:
- ingresses/status
verbs:
- update
- apiGroups:
- networking.k8s.io
resources:
- ingressclasses
verbs:
- get
- list
- watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
rules:
- apiGroups:
- admissionregistration.k8s.io
resources:
- validatingwebhookconfigurations
verbs:
- get
- update
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
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: 1.3.1
name: ingress-nginx
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: ingress-nginx
subjects:
- kind: ServiceAccount
name: ingress-nginx
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
namespace: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: ingress-nginx-admission
subjects:
- kind: ServiceAccount
name: ingress-nginx-admission
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
labels:
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ingress-nginx
subjects:
- kind: ServiceAccount
name: ingress-nginx
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: ingress-nginx-admission
subjects:
- kind: ServiceAccount
name: ingress-nginx-admission
namespace: ingress-nginx
---
apiVersion: v1
data:
allow-snippet-annotations: "true"
kind: ConfigMap
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: 1.3.1
name: ingress-nginx-controller
namespace: ingress-nginx
---
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: 1.3.1
name: ingress-nginx-controller
namespace: ingress-nginx
spec:
externalTrafficPolicy: Local
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: NodePort
---
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: 1.3.1
name: ingress-nginx-controller-admission
namespace: ingress-nginx
spec:
ports:
- appProtocol: https
name: https-webhook
port: 443
targetPort: webhook
selector:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
type: ClusterIP
---
apiVersion: apps/v1
kind: Deployment
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: 1.3.1
name: ingress-nginx-controller
namespace: ingress-nginx
spec:
minReadySeconds: 0
revisionHistoryLimit: 10
selector:
matchLabels:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
template:
metadata:
labels:
app.kubernetes.io/component: controller
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
spec:
containers:
- args:
- /nginx-ingress-controller
- --publish-service=$(POD_NAMESPACE)/ingress-nginx-controller
- --election-id=ingress-controller-leader
- --controller-class=k8s.io/ingress-nginx
- --ingress-class=nginx
- --configmap=$(POD_NAMESPACE)/ingress-nginx-controller
- --validating-webhook=:8443
- --validating-webhook-certificate=/usr/local/certificates/cert
- --validating-webhook-key=/usr/local/certificates/key
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
- name: LD_PRELOAD
value: /usr/local/lib/libmimalloc.so
image: dyrnq/ingress-nginx-controller:v1.3.1
imagePullPolicy: IfNotPresent
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
livenessProbe:
failureThreshold: 5
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
name: controller
ports:
- containerPort: 80
name: http
protocol: TCP
- containerPort: 443
name: https
protocol: TCP
- containerPort: 8443
name: webhook
protocol: TCP
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
resources:
requests:
cpu: 100m
memory: 90Mi
securityContext:
allowPrivilegeEscalation: true
capabilities:
add:
- NET_BIND_SERVICE
drop:
- ALL
runAsUser: 101
volumeMounts:
- mountPath: /usr/local/certificates/
name: webhook-cert
readOnly: true
dnsPolicy: ClusterFirst
nodeSelector:
kubernetes.io/os: linux
serviceAccountName: ingress-nginx
terminationGracePeriodSeconds: 300
volumes:
- name: webhook-cert
secret:
secretName: ingress-nginx-admission
---
apiVersion: batch/v1
kind: Job
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission-create
namespace: ingress-nginx
spec:
template:
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission-create
spec:
containers:
- args:
- create
- --host=ingress-nginx-controller-admission,ingress-nginx-controller-admission.$(POD_NAMESPACE).svc
- --namespace=$(POD_NAMESPACE)
- --secret-name=ingress-nginx-admission
env:
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
image: dyrnq/kube-webhook-certgen:v1.3.0
imagePullPolicy: IfNotPresent
name: create
securityContext:
allowPrivilegeEscalation: false
nodeSelector:
kubernetes.io/os: linux
restartPolicy: OnFailure
securityContext:
fsGroup: 2000
runAsNonRoot: true
runAsUser: 2000
serviceAccountName: ingress-nginx-admission
---
apiVersion: batch/v1
kind: Job
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission-patch
namespace: ingress-nginx
spec:
template:
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission-patch
spec:
containers:
- args:
- patch
- --webhook-name=ingress-nginx-admission
- --namespace=$(POD_NAMESPACE)
- --patch-mutating=false
- --secret-name=ingress-nginx-admission
- --patch-failure-policy=Fail
env:
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
image: dyrnq/kube-webhook-certgen:v1.3.0
imagePullPolicy: IfNotPresent
name: patch
securityContext:
allowPrivilegeEscalation: false
nodeSelector:
kubernetes.io/os: linux
restartPolicy: OnFailure
securityContext:
fsGroup: 2000
runAsNonRoot: true
runAsUser: 2000
serviceAccountName: ingress-nginx-admission
---
apiVersion: networking.k8s.io/v1
kind: IngressClass
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: 1.3.1
name: nginx
spec:
controller: k8s.io/ingress-nginx
---
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingWebhookConfiguration
metadata:
labels:
app.kubernetes.io/component: admission-webhook
app.kubernetes.io/instance: ingress-nginx
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
app.kubernetes.io/version: 1.3.1
name: ingress-nginx-admission
webhooks:
- admissionReviewVersions:
- v1
clientConfig:
service:
name: ingress-nginx-controller-admission
namespace: ingress-nginx
path: /networking/v1/ingresses
failurePolicy: Fail
matchPolicy: Equivalent
name: validate.nginx.ingress.kubernetes.io
rules:
- apiGroups:
- networking.k8s.io
apiVersions:
- v1
operations:
- CREATE
- UPDATE
resources:
- ingresses
sideEffects: None
准备service与pod
[root@k8s-master ingress-controller]# cat tomcat-nginx.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
namespace: dev
spec:
replicas: 3
selector:
matchLabels:
app: nginx-pod
template:
metadata:
labels:
app: nginx-pod
spec:
containers:
- name: nginx
image: nginx:1.17.1
ports:
- containerPort: 80
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: tomcat-deployment
namespace: dev
spec:
replicas: 3
selector:
matchLabels:
app: tomcat-pod
template:
metadata:
labels:
app: tomcat-pod
spec:
containers:
- name: tomcat
image: tomcat:8.5-jre10-slim
ports:
- containerPort: 8080
---
apiVersion: v1
kind: Service
metadata:
name: nginx-service
namespace: dev
spec:
selector:
app: nginx-pod
type: ClusterIP
ports:
- port: 80
targetPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: tomcat-service
namespace: dev
spec:
selector:
app: tomcat-pod
type: ClusterIP
ports:
- port: 8080
targetPort: 8080
创建pod并且运行
# 创建
[root@k8s-master ingress-controller]# kubectl apply -f tomcat-nginx.yaml
deployment.apps/nginx-deployment created
deployment.apps/tomcat-deployment created
service/nginx-service created
service/tomcat-service created
[root@k8s-master ingress-controller]#
# 查看
[root@k8s-master ingress-controller]# kubectl get svc -n devNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx-service ClusterIP 10.100.5.73 <none> 80/TCP 74s
tomcat-service ClusterIP 10.100.153.3 <none> 8080/TCP 74s
[root@k8s-master ingress-controller]# kubectl get -f tomcat-nginx.yaml
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-deployment 3/3 3 3 83s
deployment.apps/tomcat-deployment 3/3 3 3 83s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/nginx-service ClusterIP 10.100.5.73 <none> 80/TCP 83s
service/tomcat-service ClusterIP 10.100.153.3 <none> 8080/TCP 83s