After installing the ftp server you can connect to it but cannot retrieve directory listings?
This happens because iptables won’t let you work in passive mode. So you need to load the “ip_conntrack_ftp” module.
You know you have this issue if you disable iptables and the FTP is working correctly.

Edit the following file:
/etc/sysconfig/iptables-config

And put this line anywhere in that file:

IPTABLES_MODULES="ip_conntrack_ftp"

Also make sure that port 21 is open. Edit the iptables file: /etc/sysconfig/iptables
Make sure you have this line in there:

-A INPUT -m state --state NEW -m tcp -p tcp --dport 21 -j ACCEPT

Now restart the firewall:

service iptables restart