Plesk FTP - Service not available

On new plesk server, i got following error while connecting through FTP.

[root@localhost /]# ftp localhost
Connected to localhost (127.0.0.1).
421 Service not available, remote server has closed connection
ftp>

The problem is due to server could not resolve it's own hostname. This can be verified with

ping `hostname`

If you can't ping the hostname, add following record into /etc/hosts file:

THE_SERVER_IP HOSTNAME

Also you can edit the DNS of the domain and add an "A" record for your host name pointing to your server base IP address.

In this case the domain was hosted on the same server, so i edited the DNS Zone file of the domain. Lets say the host name of the server is server22.bizhat.com, i edited DNS Zone file of the domain bizhat.com

vi /var/named/run-root/var/bizhat.com

Added A record at the edit of the file

server22.bizhat.com.            IN A    72.22.81.106

After adding the DNS entry, you need to restart named.

[root@localhost var]# service named restart
Stopping named:                                            [  OK  ]
Starting named:                                            [  OK  ]
[root@localhost var]#

Now the FTP start working.