RT-N66U Merlin firmware restricting access to routers FTP

[lauris_maps]

Dear readers,

I have searched all over the forum but was not able to find answer for my question.

I am using Merlin's RT-N66U_3.0.0.4_374.34_2 and I want to use USB Application - FTP Share to give FTP access to my USB drive. BUT I want to limit access to single IP.

I have managed to access JFFS. My scripts directory is currently empty. Which file should I create nat-start or firewall-start?
What I need to write inside to limit access to my ftp service for a single IP address?

Thank you in advance!

Best regards
Lauris

 

[lauris_maps]

Did I ask my question improperly or it is not possible?

Still no answer
Did I ask my question improperly or it is not possible?