运行一个nodejs服务，先发布为deployment，然后创建service，让集群外可以访问
问题来源
海口-老男人 17:42:43
就是我要运行一个nodejs服务，先发布为deployment，然后创建service，让集群外可以访问
旧报纸 17:43:35
也就是 你的需求为 一个app 用delployment 发布 然后service 然后 代理 对吧
解决方案：
部署traefik
发布deployment pod
创建service
traefik 代理service
外部访问
环境
docker 19.03.5
kubernetes 1.17.2
traefik部署
为什么选择 traefik，抛弃nginx:
https://www.php.cn/nginx/422461.html
特别说明：traefik 2.1 版本更新了灰色发布和流量复制功能 为容器/微服务而生
traefik 官网写的都很不错了 附带一篇 快速入门博文：https://www.qikqiak.com/post/traefik-2.1-101/
建议部署traefik 不要用上述链接的方案
注意：这里 Traefik 是部署在 assembly Namespace 下，如果不是需要修改下面部署文件中的 Namespace 属性。
traefik-crd.yaml
在 traefik v2.1 版本后，开始使用 CRD（Custom Resource Definition）来完成路由配置等，所以需要提前创建 CRD 资源。
# cat traefik-crd.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-16
#FileName: traefik-crd.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
## IngressRoute
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: ingressroutes.traefik.containo.us
spec:
scope: Namespaced
group: traefik.containo.us
version: v1alpha1
names:
kind: IngressRoute
plural: ingressroutes
singular: ingressroute
---
## IngressRouteTCP
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: ingressroutetcps.traefik.containo.us
spec:
scope: Namespaced
group: traefik.containo.us
version: v1alpha1
names:
kind: IngressRouteTCP
plural: ingressroutetcps
singular: ingressroutetcp
---
## Middleware
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: middlewares.traefik.containo.us
spec:
scope: Namespaced
group: traefik.containo.us
version: v1alpha1
names:
kind: Middleware
plural: middlewares
singular: middleware
---
## TLSOption
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: tlsoptions.traefik.containo.us
spec:
scope: Namespaced
group: traefik.containo.us
version: v1alpha1
names:
kind: TLSOption
plural: tlsoptions
singular: tlsoption
---
## TraefikService
apiVersion: apiextensions.k8s.io/v1beta1
kind: CustomResourceDefinition
metadata:
name: traefikservices.traefik.containo.us
spec:
scope: Namespaced
group: traefik.containo.us
version: v1alpha1
names:
kind: TraefikService
plural: traefikservices
singular: traefikservice
创建RBAC权限
Traefik 需要一定的权限，所以这里提前创建好 Traefik ServiceAccount 并分配一定的权限。
# cat traefik-rbac.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-16
#FileName: traefik-rbac.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
## ServiceAccount
apiVersion: v1
kind: ServiceAccount
metadata:
namespace: kube-system
name: traefik-ingress-controller
---
## ClusterRole
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: traefik-ingress-controller
rules:
- apiGroups: [""]
resources: ["services","endpoints","secrets"]
verbs: ["get","list","watch"]
- apiGroups: ["extensions"]
resources: ["ingresses"]
verbs: ["get","list","watch"]
- apiGroups: ["extensions"]
resources: ["ingresses/status"]
verbs: ["update"]
- apiGroups: ["traefik.containo.us"]
resources: ["middlewares"]
verbs: ["get","list","watch"]
- apiGroups: ["traefik.containo.us"]
resources: ["ingressroutes"]
verbs: ["get","list","watch"]
- apiGroups: ["traefik.containo.us"]
resources: ["ingressroutetcps"]
verbs: ["get","list","watch"]
- apiGroups: ["traefik.containo.us"]
resources: ["tlsoptions"]
verbs: ["get","list","watch"]
- apiGroups: ["traefik.containo.us"]
resources: ["traefikservices"]
verbs: ["get","list","watch"]
---
## ClusterRoleBinding
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: traefik-ingress-controller
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: traefik-ingress-controller
subjects:
- kind: ServiceAccount
name: traefik-ingress-controller
namespace: kube-system
创建traefik配置文件
由于 Traefik 配置很多，通过 CLI 定义不是很方便，一般时候选择将其配置选项放到配置文件中，然后存入 ConfigMap，将其挂入 traefik 中。
traefik-config.yaml
# cat traefik-config.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-16
#FileName: traefik-config.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
kind: ConfigMap
apiVersion: v1
metadata:
name: traefik-config
namespace: kube-system
data:
traefik.yaml: |-
ping: "" ## 启用 Ping
serversTransport:
insecureSkipVerify: true ## Traefik 忽略验证代理服务的 TLS 证书
api:
insecure: true ## 允许 HTTP 方式访问 API
dashboard: true ## 启用 Dashboard
debug: false ## 启用 Debug 调试模式
metrics:
prometheus: "" ## 配置 Prometheus 监控指标数据，并使用默认配置
entryPoints:
web:
address: ":80" ## 配置 80 端口，并设置入口名称为 web
websecure:
address: ":443" ## 配置 443 端口，并设置入口名称为 websecure
redis:
address: ":663"
providers:
kubernetesCRD: "" ## 启用 Kubernetes CRD 方式来配置路由规则
kubernetesIngress: "" ## 启动 Kubernetes Ingress 方式来配置路由规则
log:
filePath: "" ## 设置调试日志文件存储路径，如果为空则输出到控制台
level: error ## 设置调试日志级别
format: json ## 设置调试日志格式
accessLog:
filePath: "" ## 设置访问日志文件存储路径，如果为空则输出到控制台
format: json ## 设置访问调试日志格式
bufferingSize: 0 ## 设置访问日志缓存行数
filters:
#statusCodes: ["200"] ## 设置只保留指定状态码范围内的访问日志
retryAttempts: true ## 设置代理访问重试失败时，保留访问日志
minDuration: 20 ## 设置保留请求时间超过指定持续时间的访问日志
fields: ## 设置访问日志中的字段是否保留（keep 保留、drop 不保留）
defaultMode: keep ## 设置默认保留访问日志字段
names: ## 针对访问日志特别字段特别配置保留模式
ClientUsername: drop
headers: ## 设置 Header 中字段是否保留
defaultMode: keep ## 设置默认保留 Header 中字段
names: ## 针对 Header 中特别字段特别配置保留模式
User-Agent: redact
Authorization: drop
Content-Type: keep
关键配置部分
entryPoints:
web:
address: ":80" ## 配置 80 端口，并设置入口名称为 web
websecure:
address: ":443" ## 配置 443 端口，并设置入口名称为 websecure
redis:
address: ":6379" ## 配置 6379 端口，并设置入口名称为 redis
部署traefik
采用daemonset这种方式部署Traefik，所以需要提前给节点设置 Label，这样当程序部署时 Pod 会自动调度到设置 Label 的节点上
traefik-deploy.yaml
kubectl label nodes 20.0.0.202 IngressProxy=true
#cat traefik-deploy.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-16
#FileName: traefik-deploy.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: v1
kind: Service
metadata:
name: traefik
namespace: kube-system
spec:
type: NodePort
ports:
- name: web
port: 80
- name: websecure
port: 443
- name: admin
port: 8080
- name: redis
port: 6379
selector:
app: traefik
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: traefik-ingress-controller
namespace: kube-system
labels:
app: traefik
spec:
selector:
matchLabels:
app: traefik
template:
metadata:
name: traefik
labels:
app: traefik
spec:
serviceAccountName: traefik-ingress-controller
terminationGracePeriodSeconds: 1
containers:
- image: traefik:v2.1.2
name: traefik-ingress-lb
ports:
- name: web
containerPort: 80
hostPort: 80 ## 将容器端口绑定所在服务器的 80 端口
- name: websecure
containerPort: 443
hostPort: 443 ## 将容器端口绑定所在服务器的 443 端口
- name: redis
containerPort: 6379
hostPort: 6379
- name: admin
containerPort: 8080 ## Traefik Dashboard 端口
resources:
limits:
cpu: 2000m
memory: 1024Mi
requests:
cpu: 1000m
memory: 1024Mi
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
args:
- --configfile=/config/traefik.yaml
volumeMounts:
- mountPath: "/config"
name: "config"
volumes:
- name: config
configMap:
name: traefik-config
tolerations: ## 设置容忍所有污点，防止节点被设置污点
- operator: "Exists"
nodeSelector: ## 设置node筛选器，在特定label的节点上启动
IngressProxy: "true"
Traefik2.1 应用已经部署完成，但是想让外部访问 Kubernetes 内部服务，还需要配置路由规则，这里开启了 Traefik Dashboard 配置，所以首先配置 Traefik Dashboard 看板的路由规则，使外部能够访问 Traefik Dashboard。
部署traefik dashboard
# cat traefik-dashboard-route.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-16
#FileName: traefik-dashboard-route.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-route
namespace: kube-system
spec:
entryPoints:
- web
routes:
- match: Host(`traefik.linux.com`)
kind: Rule
services:
- name: traefik
port: 8080
本地host解析
其实到这里 已经能基本看出traefik是如何进行代理的了
apiVersion: v1
kind: Service
metadata:
name: traefik
namespace: kube-system
spec:
type: NodePort
ports:
- name: web
port: 80
- name: websecure
port: 443
- name: admin
port: 8080
selector:
app: traefik
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: traefik-dashboard-route
namespace: kube-system
spec:
entryPoints:
- web //入口
routes:
- match: Host(`traefik.linux.com`) //外部访问域名
kind: Rule
services:
- name: traefik //service.selector
port: 8080 //service.ports
代理一个deployment pod
问题要求是: 部署一个app 用delployment 发布 然后service 然后 代理
端口是3009
那这里就用个应用实验吧 这里我随便用个prometheus 应用吧
[root@bs-k8s-master01 prometheus]# cat prometheus-cm.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-20
#FileName: prometheus-cm.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: v1
kind: ConfigMap
metadata:
name: prometheus-config
namespace: assembly
data:
prometheus.yml: |
global:
scrape_interval: 15s
scrape_timeout: 15s
alerting:
alertmanagers:
- static_configs:
- targets: ["alertmanager-svc:9093"]
rule_files:
- /etc/prometheus/rules.yaml
scrape_configs:
- job_name: 'prometheus'
static_configs:
- targets: ['localhost:9090']
- job_name: 'traefik'
static_configs:
- targets: ['traefik.kube-system.svc.cluster.local:8080']
- job_name: "kubernetes-nodes"
kubernetes_sd_configs:
- role: node
relabel_configs:
- source_labels: [__address__]
regex: '(.*):10250'
replacement: '${1}:9100'
target_label: __address__
action: replace
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- job_name: 'kubernetes-kubelet'
kubernetes_sd_configs:
- role: node
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
insecure_skip_verify: true
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- job_name: "kubernetes-apiserver"
kubernetes_sd_configs:
- role: endpoints
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- source_labels: [__meta_kubernetes_namespace, __meta_kubernetes_service_name, __meta_kubernetes_endpoint_port_name]
action: keep
regex: default;kubernetes;https
- job_name: "kubernetes-scheduler"
kubernetes_sd_configs:
- role: endpoints
- job_name: 'kubernetes-cadvisor'
kubernetes_sd_configs:
- role: node
scheme: https
tls_config:
ca_file: /var/run/secrets/kubernetes.io/serviceaccount/ca.crt
bearer_token_file: /var/run/secrets/kubernetes.io/serviceaccount/token
relabel_configs:
- action: labelmap
regex: __meta_kubernetes_node_label_(.+)
- target_label: __address__
replacement: kubernetes.default.svc:443
- source_labels: [__meta_kubernetes_node_name]
regex: (.+)
target_label: __metrics_path__
replacement: /api/v1/nodes/${1}/proxy/metrics/cadvisor
- job_name: 'kubernetes-service-endpoints'
kubernetes_sd_configs:
- role: endpoints
relabel_configs:
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
action: keep
regex: true
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]
action: replace
target_label: __scheme__
regex: (https?)
- source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
action: replace
target_label: __metrics_path__
regex: (.+)
- source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
action: replace
target_label: __address__
regex: ([^:]+)(?::\d+)?;(\d+)
replacement: $1:$2
- action: labelmap
regex: __meta_kubernetes_service_label_(.+)
- source_labels: [__meta_kubernetes_namespace]
action: replace
target_label: kubernetes_namespace
- source_labels: [__meta_kubernetes_service_name]
action: replace
target_label: kubernetes_name
rules.yaml: |
groups:
- name: test-rule
rules:
- alert: NodeMemoryUsage
expr: (sum(node_memory_MemTotal_bytes) - sum(node_memory_MemFree_bytes + node_memory_Buffers_bytes+node_memory_Cached_bytes)) / sum(node_memory_MemTotal_bytes) * 100 > 5
for: 2m
labels:
team: node
annotations:
summary: "{{$labels.instance}}: High Memory usage detected"
description: "{{$labels.instance}}: Memory usage is above 80% (current value is: {{ $value }}"
[root@bs-k8s-master01 prometheus]# cat prometheus-rbac.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-20
#FileName: prometheus-rbac.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: v1
kind: ServiceAccount
metadata:
name: prometheus
namespace: assembly
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: prometheus
rules:
- apiGroups:
- ""
resources:
- nodes
- services
- endpoints
- pods
- nodes/proxy
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- configmaps
- nodes/metrics
verbs:
- get
- nonResourceURLs:
- /metrics
verbs:
- get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: prometheus
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: prometheus
subjects:
- kind: ServiceAccount
name: prometheus
namespace: assembly
# cat prometheus-deploy.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-20
#FileName: prometheus-deploy.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: apps/v1
kind: Deployment
metadata:
name: prometheus
namespace: assembly
labels:
app: prometheus
spec:
selector:
matchLabels:
app: prometheus
template:
metadata:
labels:
app: prometheus
spec:
imagePullSecrets:
- name: k8s-harbor-login
serviceAccountName: prometheus
containers:
- image: harbor.linux.com/prometheus/prometheus:v2.4.3
name: prometheus
command:
- "/bin/prometheus"
args:
- "--config.file=/etc/prometheus/prometheus.yml"
- "--storage.tsdb.path=/prometheus"
- "--storage.tsdb.retention=24h"
- "--web.enable-admin-api" # 控制对admin HTTP API的访问，其中包括删除时间序列等功能
- "--web.enable-lifecycle" # 支持热更新，直接执行localhost:9090/-/reload立即生效
ports:
- containerPort: 9090
protocol: TCP
name: http
volumeMounts:
- mountPath: "/prometheus"
subPath: prometheus
name: data
- mountPath: "/etc/prometheus"
name: config-volume
resources:
requests:
cpu: 100m
memory: 512Mi
limits:
cpu: 100m
memory: 512Mi
securityContext:
runAsUser: 0
volumes:
- name: data
persistentVolumeClaim:
claimName: prometheus-pvc
- configMap:
name: prometheus-config
name: config-volume
nodeSelector: ## 设置node筛选器，在特定label的节点上启动
prometheus: "true"
[root@bs-k8s-master01 prometheus]# cat prometheus-svc.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-20
#FileName: prometheus-svc.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: v1
kind: Service
metadata:
name: prometheus
namespace: assembly
labels:
app: prometheus
spec:
selector:
app: prometheus
type: NodePort
ports:
- name: web
port: 9090
targetPort: http
[root@bs-k8s-master01 prometheus]# cat prometheus-ingressroute.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-03-20
#FileName: prometheus-ingressroute.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: prometheus
namespace: assembly
spec:
entryPoints:
- web
routes:
- match: Host(`prometheus.linux.com`)
kind: Rule
services:
- name: prometheus
port: 9090
验证
显然已经代理成功了 本地hosts解析
还是没得问题的
运行一个nodejs服务，先发布为deployment，然后创建service，让集群外可以访问的更多相关文章
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