Linux Redhat open a port in the firewall

The server successfully listens to a port (such as 5500), but the outside connection does not come in, telnet its port is not through, the solution is as follows (under the root user):

$/sbin/iptables-i input-p tcp--dport 5500-j ACCEPT #开启89端口
$/etc/rc.d/init.d/iptables Save #保存配置
$/etc/rc.d/init.d/iptables Restart #重启服务

See if the port is open
$/etc/init.d/iptables Status
Table: Filter
Chain INPUT (Policy ACCEPT)
Num Target prot opt source destination
1 ACCEPT TCP--0.0.0.0/0 0.0.0.0/0 TCP DPT:5500
2 Rh-firewall-1-input All--0.0.0.0/0 0.0.0.0/0
...

Reconnect successful!

Linux Redhat open a port in the firewall