nginx代理tomcat时，tomcat获取的客户端不是客户端传过来的ip。

原因分析：
nginx作为代理服务器先拦截客户端发来的请求，它再以localhost的身份转发给tomcat去处理。

解决办法：
在nginx配置中的location节点中添加：
 

代码示例:

proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header REMOTE-HOST $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
java中这样获取远程ip地址：
 

代码示例:

public static String getIpAddr(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.getRemoteAddr(); 
 } 
 return ip; 
}