Nginx反向代理后获取用户真实IP地址

问题描述：nginx集群后无法获取用户真实的IP地址，得到的一直都是前端代理服务器Nginx的地址
有2台Nginx服务器，1台代理nacos集群，一台代理vue前端项目。
在登录前端页面时一直无法获取到真实的用户IP地址，获取到的是代理前端服务器的地址

解决方法：

在代理的后端地址中加上如下代码：
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

完整代码：

       location /api/ {
        proxy_set_header   Host  $host;
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_pass  http://xxxxxxx:8080/;  //代理的后端接口地址
     }

最后：重启nginx

service nginx restart

docker :
docker restart xxxx

java获取IP地址：

public String getRequestIp(HttpServletRequest request) {
    String ip = request.getHeader("x-forwarded-for");
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
        ip = request.getHeader("Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
        ip = request.getHeader("WL-Proxy-Client-IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
        ip = request.getHeader("HTTP_CLIENT_IP");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
        ip = request.getHeader("HTTP_X_FORWARDED_FOR");
    }
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
        ip = request.getRemoteAddr();
    }
    return ip;
}