[root@localhost ~]# cat /usr/local/nginx/conf/nginx.conf
....http {    include       mime.types;    default_type  application/octet-stream;    sendfile        on;    keepalive_timeout  65;    limit_conn_zone $binary_remote_addr zone=addr:10m;    # 用于设置共享内存区域，addr 是共享内存区域的名称，10m 表示共享内存区域的大小    server {        listen       80;        server_name  www.abc.com;        location / {            root   html/www;            index  index.html index.htm;            limit_conn addr 1;     # 限制单个IP的并发连接数为1        }    }}

....http {    include       mime.types;    default_type  application/octet-stream;    sendfile        on;    keepalive_timeout  65;    limit_conn_zone $server_name zone=perserver:10m;    server {        listen       80;        server_name  www.abc.com;        location / {            root   html/www;            index  index.html index.htm;            limit_conn perserver 2;        # 设置虚拟主机连接数为2        }    }}