解決專案遷移至Kubernetes叢集中的代理問題
阿新 • • 發佈：2020-04-22
解決專案遷移至Kubernetes叢集中的代理問題
隨著Kubernetes技術的日益成熟，越來越多的企業選擇用Kubernetes叢集來管理專案。新專案還好，可以選擇合適的叢集規模從零開始構建專案；舊專案遷移進Kubernetes叢集就需要考慮很多因素，畢竟專案不能中斷時間過久。
問題來源
近日在做專案遷移至Kubernetes叢集時，遇到了一件有意思的問題：因為開發用的dubbo版本過低，在zookeeper註冊不上，需要開發升級dobbo，然後在打包成映象，所以要先把nodejs遷移進Kubernets叢集。因為是部分業務遷移進Kubernets叢集，所以要在traefik 前面還得加一層代理Nginx(Nginx為舊業務的入口，反向代理後面的微服務，阿里雲的slb指向nginx，等到業務全部遷移完畢，slb就指向traefik)。此種架構為雙層代理，即Slb-->Nginx-->Traefik-->Service 。
圖解
解決方案：
- 遷移至k8s叢集的業務走Nodeport，Nginx --> Nodeport。業務應用直接Nodeport，不好管理，1萬臺機器的時候 不能也Nodeport吧，埠自己要規劃，機器多了 每個機器還都暴露埠，想想都不現實
- 遷移至k8s叢集的業務走Clusterip，Nginx --> Traefik --> Service。這種方式合理。
解決問題
總不能拿生產環境來寫博文吧，用虛機講明。其實把虛機和生產機也就網路環境存在差別。
思路分析
- 部署k8s叢集
- 部署nginx
- 部署traefik
- 部署應用
- 聯調聯試
部署k8s叢集
使用我之前的博文部署方法：https://www.cnblogs.com/zisefeizhu/p/12505117.html
部署nginx
下載必要的元件
# hostname -I 20.0.0.101 # cat /etc/redhat-release CentOS Linux release 7.6.1810 (Core) # uname -a Linux fuxi-node02-101 4.4.186-1.el7.elrepo.x86_64 #1 SMP Sun Jul 21 04:06:52 EDT 2019 x86_64 x86_64 x86_64 GNU/Linux # wget http://nginx.org/download/nginx-1.10.2.tar.gz # wget http://www.openssl.org/source/openssl-fips-2.0.10.tar.gz # wget http://zlib.net/zlib-1.2.11.tar.gz # wget https://ftp.pcre.org/pub/pcre/pcre-8.40.tar.gz # yum install gcc-c++
配置-編譯-安裝軟體
# tar zxvf openssl-fips-2.0.10.tar.gz
# cd openssl-fips-2.0.10/
# ./config && make && make install
# cd ..
# ll
tar zxvf pcre-8.40.tar.gz
# cd pcre-8.40/
# ./configure && make && make install
# tar zxvf zlib-1.2.11.tar.gz
# cd zlib-1.2.11/
# ./configure && make && make install
# tar zxvf nginx-1.10.2.tar.gz
# cd nginx-1.10.2/
#./configure --with-http_stub_status_module --prefix=/opt/nginx
# make && make install
啟動Nginx
# pwd
/opt/nginx
# ll
總用量 4
drwx------ 2 nobody root 6 4月 22 11:30 client_body_temp
drwxr-xr-x 2 root root 4096 4月 22 12:53 conf
drwx------ 2 nobody root 6 4月 22 11:30 fastcgi_temp
drwxr-xr-x 2 root root 40 4月 22 11:29 html
drwxr-xr-x 2 root root 41 4月 22 14:24 logs
drwx------ 2 nobody root 6 4月 22 11:30 proxy_temp
drwxr-xr-x 2 root root 19 4月 22 11:29 sbin
drwx------ 2 nobody root 6 4月 22 11:30 scgi_temp
drwx------ 2 nobody root 6 4月 22 11:30 uwsgi_temp
# sbin/nginx
traefik 部署
https://www.cnblogs.com/zisefeizhu/p/12692979.html
環境檢查
# kubectl get pods,svc -A | grep traefik
kube-system pod/traefik-ingress-controller-z5qd7 1/1 Running 0 136m
kube-system service/traefik ClusterIP 10.68.251.132 <none> 80/TCP,443/TCP,8080/TCP 4h14m
瀏覽器訪問
部署應用
這裡的測試應用選擇containous/whoami映象
測試應用部署
# cat whoami.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-04-22
#FileName: whoami.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): 2020 All rights reserved
###########################################################################
apiVersion: v1
kind: Service
metadata:
name: whoami
spec:
ports:
- protocol: TCP
name: web
port: 80
selector:
app: whoami
---
kind: Deployment
apiVersion: apps/v1
metadata:
name: whoami
labels:
app: whoami
spec:
replicas: 2
selector:
matchLabels:
app: whoami
template:
metadata:
labels:
app: whoami
spec:
containers:
- name: whoami
image: containous/whoami
ports:
- name: web
containerPort: 80
# kubectl get svc,pod
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/whoami ClusterIP 10.68.109.151 <none> 80/TCP 3h30m
NAME READY STATUS RESTARTS AGE
pod/whoami-bd6b677dc-jvqc2 1/1 Running 0 3h30m
pod/whoami-bd6b677dc-lvcxp 1/1 Running 0 3h30m
聯調聯試
因為選擇的解決問題的方案是：nginx --> traefik --> service
- traefik -->service
- nginx --> traefik
- nginx --> service
traefik --> service
使用traefik 代理測試應用的資源清單：
# cat traefik-whoami.yaml
##########################################################################
#Author: zisefeizhu
#QQ: 2********0
#Date: 2020-04-22
#FileName: traefik-whoami.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: simpleingressroute
spec:
entryPoints:
- web
routes:
- match: Host(`who.linux.com`) && PathPrefix(`/notls`)
kind: Rule
services:
- name: whoami
port: 80
本地hosts解析
traefik介面觀察是代理成功：
訪問who.linux.com/notls
nginx --> traefik
# cat conf/nginx.conf
user nobody;
worker_processes 4;
events {
use epoll;
worker_connections 2048;
}
http {
upstream app {
server 20.0.0.202;
}
server {
listen 80;
# server_name who2.linux.com;
access_log logs/access.log;
error_log logs/error.log;
location / {
proxy_set_header X-Forwarded-For $remote_addr;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $host;
proxy_headers_hash_max_size 51200;
proxy_headers_hash_bucket_size 6400;
proxy_redirect off;
proxy_read_timeout 600;
proxy_connect_timeout 600;
proxy_pass http://app;
}
}
}
# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
20.0.0.202 who.linux.com //k8s叢集traefik所落節點，其實K8s任意節點都隨便拉
# curl -iL who.linux.com/notls
HTTP/1.1 200 OK
Content-Length: 388
Content-Type: text/plain; charset=utf-8
Date: Wed, 22 Apr 2020 07:33:52 GMT
Hostname: whoami-bd6b677dc-lvcxp
IP: 127.0.0.1
IP: 172.20.46.67
RemoteAddr: 172.20.177.153:58168
GET /notls HTTP/1.1
Host: who.linux.com
User-Agent: curl/7.29.0
Accept: */*
Accept-Encoding: gzip
X-Forwarded-For: 20.0.0.101
X-Forwarded-Host: who.linux.com
X-Forwarded-Port: 80
X-Forwarded-Proto: http
X-Forwarded-Server: traefik-ingress-controller-z5qd7
X-Real-Ip: 20.0.0.101
nginx要是不熟悉就看這大佬的博文吧：https://www.cnblogs.com/kevingrace/p/6095027.html
nginx --> service
# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
20.0.0.101 who.linux.com
# curl -iL who.linux.com/notls
HTTP/1.1 200 OK //響應資訊
Server: nginx/1.10.2 //響應服務
Date: Wed, 22 Apr 2020 07:27:46 GMT
Content-Type: text/plain; charset=utf-8
Content-Length: 389
Connection: keep-alive
Hostname: whoami-bd6b677dc-jvqc2
IP: 127.0.0.1
IP: 172.20.46.111
RemoteAddr: 172.20.177.153:38298
GET /notls HTTP/1.1
Host: who.linux.com
User-Agent: curl/7.29.0
Accept: */*
Accept-Encoding: gzip
X-Forwarded-For: 20.0.0.101
X-Forwarded-Host: who.linux.com
X-Forwarded-Port: 80
X-Forwarded-Proto: http
X-Forwarded-Server: traefik-ingress-controller-z5qd7
X-Real-Ip: 20.0.0.101
nginx日誌
# tail -f access.log
20.0.0.101 - - [22/Apr/2020:15:28:28 +0800] "GET /notls HTTP/1.1" 200 389 "-" "curl/7.29.0"
瀏覽器測試
繼續測試
把traefik應用給關了，然後再測試
# kubectl delete -f .
configmap "traefik-config" deleted
customresourcedefinition.apiextensions.k8s.io "ingressroutes.traefik.containo.us" deleted
customresourcedefinition.apiextensions.k8s.io "ingressroutetcps.traefik.containo.us" deleted
customresourcedefinition.apiextensions.k8s.io "middlewares.traefik.containo.us" deleted
customresourcedefinition.apiextensions.k8s.io "tlsoptions.traefik.containo.us" deleted
customresourcedefinition.apiextensions.k8s.io "traefikservices.traefik.containo.us" deleted
ingressroute.traefik.containo.us "traefik-dashboard-route" deleted
service "traefik" deleted
daemonset.apps "traefik-ingress-controller" deleted
serviceaccount "traefik-ingress-controller" deleted
clusterrole.rbac.authorization.k8s.io "traefik-ingress-controller" deleted
clusterrolebinding.rbac.authorization.k8s.io "traefik-ingress-controller" deleted
# kubectl delete -f traefik-whoami.yaml //關閉whoami traefik代理
ingressroute.traefik.containo.us "simpleingressroute" deleted
沒得說了 測試結果很明確了：訪問who.linux.com 流量走向：nginx-->traefik --> service