Other than letting a specific ip address to access your FTP server via security policy in ASA, you would also need to look into the FTP software itself at the server. By right it should have some sort of console or management capabilities to let only specific number of users FTP in or user time limit.
Login to the FXOS chassis manager.
Direct your browser to https://hostname/, and log-in using the user-name and password.
Go to Help > About and check the current version:
Check the current version availa...
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...