Node.js 无法联系到该站点的节点7

我是node js新手，这是我第一次尝试在centos7服务器上运行node server。 这是我的文件中的代码：

const express = require('express');
const app = express();


//setting
app.set('port', process.env.PORT || 3000);



app.listen(app.get('port'), () => {
    console.log('server on port ', app.get('port'));
});

由于某些原因，我在尝试加载http://********:3000时遇到无法访问此站点的错误

我忽略了这一点，但无法解决错误

我将这个字符串放在终端iptables-A INPUT-p tcp-dport 3000-j ACCEPT中

这是站点iptables-L输出

---

问题是我没有打开服务器防火墙中的端口

我所做的是将端口3000设置为MPPublic：

[root@aaa~]firewall cmd-zone=public-add port=3000/tcp-永久 然后我对防火墙重新编码：

[root@aaa~]防火墙命令-重新加载

这就是所有的人

Chain INPUT (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere             ctstate RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere
INPUT_direct  all  --  anywhere             anywhere
INPUT_ZONES_SOURCE  all  --  anywhere             anywhere
INPUT_ZONES  all  --  anywhere             anywhere
DROP       all  --  anywhere             anywhere             ctstate INVALID
REJECT     all  --  anywhere             anywhere             reject-with icmp-host-prohibited
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:hbci
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:origo-native

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere             ctstate RELATED,ESTABLISHED
ACCEPT     all  --  anywhere             anywhere
FORWARD_direct  all  --  anywhere             anywhere
FORWARD_IN_ZONES_SOURCE  all  --  anywhere             anywhere
FORWARD_IN_ZONES  all  --  anywhere             anywhere
FORWARD_OUT_ZONES_SOURCE  all  --  anywhere             anywhere
FORWARD_OUT_ZONES  all  --  anywhere             anywhere
DROP       all  --  anywhere             anywhere             ctstate INVALID
REJECT     all  --  anywhere             anywhere             reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
OUTPUT_direct  all  --  anywhere             anywhere

Chain FORWARD_IN_ZONES (1 references)
target     prot opt source               destination
FWDI_public  all  --  anywhere             anywhere            [goto]
FWDI_public  all  --  anywhere             anywhere            [goto]

Chain FORWARD_IN_ZONES_SOURCE (1 references)
target     prot opt source               destination

Chain FORWARD_OUT_ZONES (1 references)
target     prot opt source               destination
FWDO_public  all  --  anywhere             anywhere            [goto]
FWDO_public  all  --  anywhere             anywhere            [goto]

Chain FORWARD_OUT_ZONES_SOURCE (1 references)
target     prot opt source               destination

Chain FORWARD_direct (1 references)
target     prot opt source               destination

Chain FWDI_public (2 references)
target     prot opt source               destination
FWDI_public_log  all  --  anywhere             anywhere
FWDI_public_deny  all  --  anywhere             anywhere
FWDI_public_allow  all  --  anywhere             anywhere
ACCEPT     icmp --  anywhere             anywhere

Chain FWDI_public_allow (1 references)
target     prot opt source               destination

Chain FWDI_public_deny (1 references)
target     prot opt source               destination

Chain FWDI_public_log (1 references)
target     prot opt source               destination

Chain FWDO_public (2 references)
target     prot opt source               destination
FWDO_public_log  all  --  anywhere             anywhere
FWDO_public_deny  all  --  anywhere             anywhere
FWDO_public_allow  all  --  anywhere             anywhere

Chain FWDO_public_allow (1 references)
target     prot opt source               destination

Chain FWDO_public_deny (1 references)
target     prot opt source               destination

Chain FWDO_public_log (1 references)
target     prot opt source               destination

Chain INPUT_ZONES (1 references)
target     prot opt source               destination
IN_public  all  --  anywhere             anywhere            [goto]
IN_public  all  --  anywhere             anywhere            [goto]

Chain INPUT_ZONES_SOURCE (1 references)
target     prot opt source               destination

Chain INPUT_direct (1 references)
target     prot opt source               destination

Chain IN_public (2 references)
target     prot opt source               destination
IN_public_log  all  --  anywhere             anywhere
IN_public_deny  all  --  anywhere             anywhere
IN_public_allow  all  --  anywhere             anywhere
ACCEPT     icmp --  anywhere             anywhere

Chain IN_public_allow (1 references)
target     prot opt source               destination
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:http ctstate NEW
ACCEPT     tcp  --  anywhere             anywhere             tcp dpt:ssh ctstate NEW

Chain IN_public_deny (1 references)
target     prot opt source               destination

Chain IN_public_log (1 references)
target     prot opt source               destination

Chain OUTPUT_direct (1 references)
target     prot opt source               destination