在Centos+nginx+wordpress环境停启动iptables 网站返回502

在Centos+nginx+wordpress环境下启动iptables 网站返回502
网站环境：Centos nginx php(wordpress)

现在的问题总结如下：
启动iptables网站返回502，关闭iptables网站打开正常

iptables 设置如下：
Chain INPUT (policy DROP 1 packets, 139 bytes)
pkts bytes target prot opt in out source destination
0 0 ACCEPT all — lo any anywhere anywhere
17 1460 ACCEPT all — any any anywhere anywhere state RELATED,ESTABLISHED
1 40 ACCEPT tcp — any any anywhere anywhere tcp dpt:ssh
0 0 ACCEPT tcp — any any anywhere anywhere tcp dpt:mysql
2 80 ACCEPT tcp — any any anywhere anywhere tcp dpt:http
0 0 ACCEPT all — lo any anywhere anywhere
0 0 ACCEPT icmp — any any anywhere anywhere
0 0 ACCEPT tcp — any any anywhere anywhere tcp dpt:pptp
0 0 ACCEPT gre — any

2本文来源gao!daima.com搞$代!码网

搞代gaodaima码any anywhere anywhere

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination

Chain OUTPUT (policy ACCEPT 16 packets, 4024 bytes)
pkts bytes target prot opt in out source destination
2 80 ACCEPT tcp — any any anywhere anywhere tcp spt:http

开启了lo，开启了80，开始了9000

在开启iptables时，静态的网页时能打开的，但是切换回wordpress是又返回502.

查看error-log都是：
2013/09/26 01:45:37 [error] 1745#0: *106 recv() failed (104: Connection reset by peer) while reading response header from upstream, client:, server: xiaobuxun.me, request: “POST /wp-admin/admin-ajax.php HTTP/1.1”, upstream: “fastcgi://127.0.0.1:9000”, host: “xiaobuxun.me”, referrer: “http://xiaobuxun.me/wp-admin/post-new.php”

我考虑是iptables的问题，是fastCGI用的9000端口没有打开，，但是我已经配置上了，为什么还是返回502，求大神指教了！！！

iptables nginx fastCGI