bool1993/keepalived

keepalived Docker镜像文档

镜像概述

本镜像集成了Keepalived和Nginx服务，旨在提供高可用的Web服务架构。通过Keepalived的VRRP（虚拟路由冗余协议）实现节点故障自动转移，结合Nginx提供Web服务和负载均衡能力，确保服务在单点故障时仍能正常运行。

核心功能与特性

• 高可用保障：基于Keepalived实现VRRP协议，支持主备节点自动切换
• Web服务能力：内置Nginx，可直接提供HTTP服务或作为反向代理
• 故障检测：通过脚本监控Nginx运行状态，异常时自动触发故障转移
• 灵活配置：支持挂载自定义Keepalived和Nginx配置文件
• 轻量级部署：基于Docker容器化部署，简化环境配置与维护

使用场景

• 需要高可用性的Web服务部署
• 负载均衡集群环境
• 关键业务系统的冗余备份方案
• 简化的高可用架构测试与演示环境

使用方法

拉取镜像

bash
docker pull docker.xuanyuan.run/bool1993/keepalived

基本运行

bash
docker run --name=keepalived_nginx -itd -p 8085:80 --restart=always docker.xuanyuan.run/bool1993/keepalived:latest

自定义配置运行

挂载本地配置文件以覆盖默认配置：

bash
docker run --name=keepalived_nginx -itd -p 8085:80 --restart=always \
  -v $PWD/keepalived.conf:/etc/keepalived/keepalived.conf \
  -v $PWD/nginx:/etc/nginx \
  -v $PWD/html:/www/html \
  docker.xuanyuan.run/bool1993/keepalived:latest

进入容器

bash
docker exec -it keepalived_nginx /bin/sh

启动服务

在容器内手动启动Nginx和Keepalived：

bash
nginx && keepalived

访问测试

服务启动后，通过以下地址访问Nginx服务：

http://localhost:8085/

基于Dockerfile构建

创建Dockerfile

dockerfile
FROM docker.xuanyuan.run/bool1993/keepalived:latest

EXPOSE 80

CMD nginx -g "daemon off;" && keepalived

构建镜像

bash
docker build -t test-keepalived .

运行自定义构建的容器

bash
docker run -it -d --name=keepalived -p 8085:80 --restart=always \
  -v $PWD/keepalived.conf:/etc/keepalived/keepalived.conf \
  -v $PWD/html:/www/html \
  -v $PWD/nginx:/etc/nginx \
  docker.xuanyuan.run/test-keepalived

配置文件说明

keepalived.conf（/etc/keepalived/keepalived.conf）

核心配置文件，定义VRRP实例和健康检查脚本：

conf
! Configuration File for keepalived
global_defs { 
    # 故障通知邮箱
    notification_email { 
        1968397477@qq.com
    }
    # 通知邮件发送地址
    notification_email_from itsection@example.com
    smtp_server mail.example.com
    # SMTP连接超时时间
    smtp_connect_timeout 30
    router_id LVS_DEVEL 
}

# Nginx健康检查脚本
vrrp_script chk_nginx {
    script "/etc/keepalived/nginx_check.sh" 
    interval 2   # 检查间隔(秒)
    weight -20   # 失败时优先级调整值
    fall 3       # 连续失败次数阈值
    rise 2       # 连续成功次数阈值
    user root    # 执行脚本的用户
}

vrrp_instance VI_1 {
    state MASTER  # 初始状态(MASTER/BACKUP)
    interface eth0  # 绑定网卡
    virtual_router_id 2  # 虚拟路由ID(主备节点需一致)
    priority 101   # 优先级(MASTER应高于BACKUP)
    advert_int 2    # 心跳间隔(秒)

    authentication {
        auth_type PASS  
        auth_pass 1111  # 认证密码(主备节点需一致)
    }

    # 虚拟IP地址
    virtual_ipaddress {
        172.17.0.2   
    }

    # 关联健康检查脚本
    track_script {
        chk_nginx
    }
}

nginx.conf（/etc/nginx/nginx.conf）

Nginx主配置文件，定义全局参数和HTTP配置：

conf
user nginx;
worker_processes auto;
pcre_jit on;
error_log /var/log/nginx/error.log warn;
include /etc/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    server_tokens off;
    client_max_body_size 1m;
    sendfile on;
    tcp_nopush on;
    ssl_protocols TLSv1.1 TLSv1.2 TLSv1.3;
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:2m;
    ssl_session_timeout 1h;
    ssl_session_tickets off;
    gzip_vary on;

    map $http_upgrade $connection_upgrade {
        default upgrade;
        '' close;
    }

    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';
    access_log /var/log/nginx/access.log main;
    include /etc/nginx/http.d/*.conf;
}

Nginx子配置（/etc/nginx/http.d/1.conf）

定义Web服务虚拟主机配置：

conf
server {
    listen       80;
    listen  [::]:80;

    location / {
        root   /www/html;
        index  index.html index.htm;
    }

    location = /404.html {
        internal;
    }
}

健康检查脚本（/etc/keepalived/nginx_check.sh）

监控Nginx运行状态，异常时尝试重启或触发故障转移：

bash
#!/bin/bash

A=`ps -C nginx --no-header |wc -l`
# 判断Nginx是否宕机，尝试重启
if [ $A -eq 0 ];then
    nginx
    # 等待3秒后再次检查
    sleep 3
    if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then
        killall keepalived  # Nginx启动失败，停止Keepalived触发切换
    fi
fi