你可以使用NginxHttpLimitZone模块来限制指定的会话或者一个IP地址的特殊情况下的并发连接。编辑nginx.conf:

1. ### Directive describes the zone, in which the session states are stored i.e. store in slimits. ###

2. ### 1m can handle 32000 sessions with 32 bytes/session, set to 5m x 32000 session ###

3. limit_zone slimits $binary_remote_addr 5m;

4. ### Control maximum number of simultaneous connections for one session i.e. ###

5. ### restricts the amount of connections from a single ip address ###

6. limit_conn slimits 5;

上面表示限制每个远程IP地址的客户端同时打开连接不能超过5个。