Ftp ACL (Access Control Lists ) – restricted FTP access
What is ACL ?
When you enable it , only selected ips have access to FTP server as a client. it is for security of FTP. if some one stole your FTP.
How to ? It is depends on your FTP provider. But if you have own linux server.
access-list 101 permit tcp any any eq 21 !--- The above line permits TCP traffic from any source, such as the FTP client, !--- FTP server destination at the FTP control port 21. access-list 101 permit tcp any eq 20 any !--- The above line permits TCP traffic from any source, such as the FTP server, !--- FTP client at FTP data port 20.
Example Document :