Envoy Tcp请求静态配置
1 准备工作
准备工作包括:
- docker-compose环境准备
- yaml及docker-compse配置文件获取(来自github/ikubernetes)
# apt install docker-compose -y
# docker pull envoyproxy/envoy-alpine:v1.21.5
# mkdir /apps/envoy -p
# cd /apps/envoy
# git clone https://github.com/ikubernetes/servicemesh_in_practise.git
# cd servicemesh_in_practise/
# ls
admin-interface eds-filesystem envoy.echo http-egress LICENSE security tls-front-proxy
cds-eds-filesystem eds-grpc front-proxy http-ingress monitoring-and-tracing tcpproxy
cluster-manager eds-rest http-connection-manager lds-cds-grpc README.md template
# git checkout develop
Branch 'develop' set up to track remote branch 'develop' from 'origin'.
Switched to a new branch 'develop'
# ls
Cluster-Manager Envoy-Basics HTTP-Connection-Manager Monitoring-and-Tracing Security
Dynamic-Configuration Envoy-Mesh LICENSE README.md template
# cd Envoy-Basics/tcp-front-proxy/
2 docker-compose配置
docker-compose定义了3个容器
- 业务容器webserver01 IP地址172.31.1.11
- 业务容器webserver02 IP地址172.31.1.12
- envoy容器 IP地址172.31.1.2
- 定义envoymesh的网桥
/apps/envoy/servicemesh_in_practise/Envoy-Basics/tcp-front-proxy# cat docker-compose.yaml
version: '3.3'
services:
envoy:
image: envoyproxy/envoy-alpine:v1.21.5
volumes:
- ./envoy.yaml:/etc/envoy/envoy.yaml
networks:
envoymesh:
ipv4_address: 172.31.1.2
aliases:
- front-proxy
depends_on:
- webserver01
- webserver02
webserver01:
image: ikubernetes/demoapp:v1.0
environment:
- PORT=8080
hostname: webserver01
networks:
envoymesh:
ipv4_address: 172.31.1.11
aliases:
- webserver01
webserver02:
image: ikubernetes/demoapp:v1.0
environment:
- PORT=8080
hostname: webserver02
networks:
envoymesh:
ipv4_address: 172.31.1.12
aliases:
- webserver02
networks:
envoymesh:
driver: bridge
ipam:
config:
- subnet: 172.31.1.0/24
3 envoy.yaml配置
envoy.yaml中定义:
- 使用的是静态配置static_resources
- 监听器监听 0.0.0.0:80 端口
- 监听器接收到请求转发给filter_chains,filter_chains串联了tcp_proxy过滤器对请求进行解码,代理给local_cluster
- clusters中定义了local_cluster,其中包含2个Endpoint,172.31.1.11:8080 和172.31.1.12:8080
static_resources:
listeners:
name: listener_0
address:
socket_address: {
address: 0.0.0.0, port_value: 80 }
filter_chains:
- filters:
- name: envoy.tcp_proxy
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.network.tcp_proxy.v3.TcpProxy
stat_prefix: tcp
cluster: local_cluster
clusters:
- name: local_cluster
connect_timeout: 0.25s
type: STATIC
lb_policy: ROUND_ROBIN
load_assignment:
cluster_name: local_cluster
endpoints:
- lb_endpoints:
- endpoint:
address:
socket_address: {
address: 172.31.1.11, port_value: 8080 }
- endpoint:
address:
socket_address: {
address: 172.31.1.12, port_value: 8080 }
4 部署并测试访问
启动docker-compose后,客户端访问172.31.1.2查看转发效果
# docker-compose up
## 客户端上执行
# curl 172.31.1.2
iKubernetes demoapp v1.0 !! ClientIP: 172.31.1.2, ServerName: webserver01, ServerIP: 172.31.1.11!
# curl 172.31.1.2
iKubernetes demoapp v1.0 !! ClientIP: 172.31.1.2, ServerName: webserver02, ServerIP: 172.31.1.12!
# curl 172.31.1.2
iKubernetes demoapp v1.0 !! ClientIP: 172.31.1.2, ServerName: webserver02, ServerIP: 172.31.1.12!
# curl 172.31.1.2
iKubernetes demoapp v1.0 !! ClientIP: 172.31.1.2, ServerName: webserver01, ServerIP: 172.31.1.11!
## docker-compose服务器上可以看到请求的记录
envoy_1 | [2022-09-23 06:36:33.256][1][info][main] [source/server/server.cc:868] starting main dispatch loop
webserver01_1 | 172.31.1.2 - - [23/Sep/2022 06:38:19] "GET / HTTP/1.1" 200 -
webserver02_1 | 172.31.1.2 - - [23/Sep/2022 06:38:20] "GET / HTTP/1.1" 200 -
webserver02_1 | 172.31.1.2 - - [23/Sep/2022 06:38:21] "GET / HTTP/1.1" 200 -
webserver01_1 | 172.31.1.2 - - [23/Sep/2022 06:38:21] "GET / HTTP/1.1" 200 -
## 测试完清理环境
# docker-compose down
5 访问流程梳理
- 当客户端访问172.31.1.2:80(docker-compose中的envoy容器),请求被转发到front-proxy的Listener上的80端口(listener中socket_address定义)
- 由filter chains定义的tcp_proxy过滤器对请求进行解码,将传输层报文通过tcp_proxy(typed_config中定义)解码到Clusters中的local_cluster
- Cluster使用轮询算法将请求转发到后端的Endpoint(clusters中socket_address字段定义)上.
