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Is it true that FTP do not works well with NAT?

How true is this statment ?

" The file transfer protocol (FTP) is another example of a protocol/application with which NAT has trouble correctly supporting . The FTP layer 3 connection addressing is also embedded (hidden) within the payload of an outgoing data packet. Some NAT application processes do not decode this FTP packet properly which leads to a failure in the FTP host connection."

Does Cisco 3620 have trouble with FTP with NAT? Thank for advise.

  • Other Network Infrastructure Subjects

Re: Is it true that FTP do not works well with NAT?

Cisco IOS does the necessary translation on the payload of the packet while doing NAT. But if the ftp is working on a non standard port, then it will ignore the payload and FTP wont work. For this to work, you need to do the following,

check this link out!