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目录
一、基本介绍
Ingress 是 Kubernetes 提供的一种服务发现机制,主要作用是为集群外部访问集群内部服务提供访问入口,通过制定 Ingress 策略管理 HTTP 路由,将集群外部的访问请求反向代理到集群内部不同 Service 对应的 Endpoint(即 Pod)上。
Ingress 具有以下特点:
- Ingress 支持七层负载均衡,仅支持 HTTP 通信规则
- Ingress 策略(rules)与 Ingress Controller 组成一个完整的 Ingress 负载均衡器
- Ingress 将外部访问请求直接反向代理到 Endpoint 上,从而跳过 kube-proxy 组件的转发,kube-proxy 不再起作用
- Ingress 对象与其反向代理的 Service 对象必须处于同一命名空间
- Ingress 通过 path 路径访问不同服务,且 “ / ” 位于最后避免其他路径被拦截
二、工作原理
- 定义 Ingress 策略:用户在 Kubernetes 集群中创建 Ingress 资源,定义如何将外部请求路由到集群内的服务
- 策略监听:Ingress Controller 监听 Ingress 资源的变化,当有新的 Ingress 资源被创建或现有资源被更新时,Ingress 控制器会读取这些规则
- 配置负载均衡器或反向代理:Ingress Controller 根据 Ingress 策略配置内部的负载均衡器或反向代理服务器(如 Nginx、HAProxy 等),设置路由规则
- 路由转发:Ingress Controller 会根据配置的策略,将请求转发到正确的服务
- 服务响应:服务处理请求并返回响应,Ingress Controller 将响应转发回请求者
三、资源清单(示例)
1、Ingress Controller
# nginx-ingress-controller.yaml
---
apiVersion: v1
kind: ConfigMap
metadata:
name: lb-develop-controller
namespace: kube-system
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
data:
allow-snippet-annotations: "true"
client-body-buffer-size: "10m"
client-body-timeout: "300"
client-header-buffer-size: "64k"
client-header-timeout: "300"
compute-full-forwarded-for: "true"
enable-access-log-for-default-backend: "true"
log-format-escape-json: "true"
log-format-upstream: "{\"@timestamp\": \"$time_iso8601\", \"nginx.name\": \"lb-develop\", \"remote_addr\": \"$remote_addr\", \"x_forwarded_for\": \"$http_x_forwarded_for\", \"x_forwarded_proto\": \"$pass_access_scheme\", \"node-forwarded-proto\": \"$http_node_forwarded_proto\", \"request_id\": \"$req_id\", \"remote_user\": \"$remote_user\", \"bytes_sent\": $bytes_sent, \"status\": $status, \"content_length\": \"$content_length\", \"scheme\":\"$scheme\", \"vhost\": \"$host\", \"request_proto\": \"$server_protocol\", \"path\": \"$uri\", \"request_uri\": \"$request_uri\", \"request_body\": \"$request_body\", \"request_query\": \"$args\", \"request_length\": $request_length, \"duration\": $request_time, \"method\": \"$request_method\", \"http_referer\": \"$http_referer\", \"http_client_source\": \"$http_client_source\", \"http_client_version\": \"$http_client_version\", \"http_user_agent\": \"$http_user_agent\", \"http_token\": \"$http_authorization\", \"http_authorization\": \"$http_authorization\", \"http_uid\": \"$http_http_uid\", \"http_device_id\": \"$http_device_id\", \"http_x_auth_user\": \"$http_x_auth_user\", \"http_x_auth_scope\": \"$http_x_auth_scope\", \"http_x_token_type\": \"$http_x_token_type\", \"http_x_auth_client\": \"$http_x_auth_client\", \"http_origin\": \"$http_origin\", \"cookie_token\": \"$cookie_access_token\", \"cookie_uid\": \"$cookie_uid\", \"k8s_ingress_name\": \"$ingress_name\", \"k8s_namespace\": \"$namespace\", \"k8s_service_name\": \"$service_name\", \"upstream_name\": \"$proxy_upstream_name\", \"upstream_addr\": \"$upstream_addr\", \"upstream_status\": \"$upstream_status\", \"upstream_response_time\": \"$upstream_response_time\"}"
proxy-add-original-uri-header: "true"
proxy-body-size: "200m"
proxy-buffer-size: "512k"
proxy-buffering: "on"
proxy-buffers-number: "8"
proxy-connect-timeout: "300"
proxy-read-timeout: "300"
proxy-send-timeout: "300"
upstream-keepalive-connections: "100"
upstream-keepalive-requests: "100"
upstream-keepalive-timeout: "30"
use-forwarded-headers: "true"
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: lb-develop
namespace: kube-system
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
automountServiceAccountToken: true
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: lb-develop
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
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: ClusterRoleBinding
metadata:
name: lb-develop
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: lb-develop
subjects:
- kind: ServiceAccount
name: lb-develop
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: lb-develop
namespace: kube-system
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
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
# TODO(Jintao Zhang)
# Once we release a new version of the controller,
# we will be able to remove the configmap related permissions
# We have used the Lease API for selection
# ref: https://github.com/kubernetes/ingress-nginx/pull/8921
- apiGroups:
- ""
resources:
- configmaps
resourceNames:
- ingress-controller-leader
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- coordination.k8s.io
resources:
- leases
resourceNames:
- ingress-controller-leader
verbs:
- get
- update
- apiGroups:
- coordination.k8s.io
resources:
- leases
verbs:
- create
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: lb-develop
namespace: kube-system
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: lb-develop
subjects:
- kind: ServiceAccount
name: lb-develop
namespace: kube-system
---
apiVersion: v1
kind: Service
metadata:
name: lb-develop-controller
namespace: kube-system
annotations:
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
spec:
type: ClusterIP
selector:
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/component: controller
ports:
- name: http
port: 80
protocol: TCP
targetPort: http
appProtocol: http
- name: https
port: 443
protocol: TCP
targetPort: https
appProtocol: https
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: lb-develop-controller
namespace: kube-system
annotations:
reloader.stakater.com/auto: "true"
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
spec:
selector:
matchLabels:
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/component: controller
template:
metadata:
labels:
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/component: controller
app: lb-develop
release: lb-develop
spec:
containers:
- name: controller
image: nginx-ingress-controller:1.2.1
imagePullPolicy: IfNotPresent
ports:
- name: http
containerPort: 80
protocol: TCP
- name: https
containerPort: 443
protocol: TCP
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
args:
- /nginx-ingress-controller
- --publish-service=$(POD_NAMESPACE)/lb-develop-controller
- --election-id=ingress-controller-leader
- --controller-class=k8s.io/ingress-nginx
- --ingress-class=lb-develop
- --configmap=$(POD_NAMESPACE)/lb-develop-controller
- --watch-ingress-without-class=true
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
runAsUser: 101
allowPrivilegeEscalation: true
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
- name: TZ
value: Asia/Shanghai
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 60
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 60
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: loadbalancer
operator: In
values:
- lb-develop
hostNetwork: true # 直接绑定主机的80端口、443端口
dnsPolicy: ClusterFirstWithHostNet # 设置对应的dns策略
serviceAccountName: lb-develop
terminationGracePeriodSeconds: 300
---
# We don't support namespaced ingressClass yet
# So a ClusterRole and a ClusterRoleBinding is required
apiVersion: networking.k8s.io/v1
kind: IngressClass
metadata:
name: lb-develop
annotations:
ingressclass.kubernetes.io/is-default-class: "true"
labels:
helm.sh/chart: ingress-nginx-4.2.5
app.kubernetes.io/name: lb-develop
app.kubernetes.io/instance: lb-develop
app.kubernetes.io/version: "1.3.1"
app.kubernetes.io/part-of: lb-develop
app.kubernetes.io/managed-by: Helm
app.kubernetes.io/component: controller
spec:
controller: k8s.io/ingress-nginx
2、Ingress 对象
- networking.k8s.io/v1 类型
# demo-ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress
namespace: kube-system
annotations:
kubernetes.io/ingress.class: "lb-develop"
spec:
ingressClassName: lb-develop
rules:
- host: xx.xx.com # 有域名情况
http:
paths:
- path: /prom
pathType: Prefix # 必须要指定
backend:
service:
name: prometheus
port:
number: 9090 # 或者name: xxxx
- path: /graf
pathType: Prefix # 必须要指定
backend:
service:
name: monitoring-grafana
port:
number: 8080
- http: # 无域名情况
paths:
- path: /nginx
pathType: Prefix # 必须要指定
backend:
service:
name: nginx
port:
number: 8080 # 或者name: xxxx
tls:
- hosts:
- xxx.xxx.com
secretName: demo-secret
标签:Ingress,lb,Kubernetes,kubernetes,app,io,develop,K8s,name
From: https://blog.csdn.net/2401_82795112/article/details/139931577