I have a basic RRAS Setup, One nic on WAN, one on LAN. Everything seems to be working ok with traffic routing except FTP. On the server if I try to FTP to a remote site it works, however clients behind the server are unable to connect using FTP. if I disable the Firewall on the Server, the clients are able to use FTP to connect to remote servers. (Pass-through the local server via RRAS/NAT) Once the Firewall is re-enabled it stops again.

Sample log:

Status: Waiting to retry...
Status: Resolving address of someftpserver.com
Status: Connecting to 1.1.1.1:21...
Error: Connection timed out
Error: Could not connect to server

I can only assume there is some setting in the firewall that i'm missing. I don't recall needing to change anything in Server 2008 R2 to allow pass-through FTP traffic.

Hi,

Thank you for the post.

I thought some IPSec (connection security) rules works when you enabled server firewall. Try to disable connection security rules or configure server to support NAT-T.
http://support.microsoft.com/kb/926179

If there are more inquiries on this issue, please feel free to let us know.

Regards

Hi,

I have the same problem. Unable to access an FTP server behind a Server Windows 2012 RRAS NAT. how to solve this problem ?

• Proposed as answer by Lythom57 Thursday, April 11, 2013 3:21 PM
• Unproposed as answer by Lythom57 Thursday, April 11, 2013 3:21 PM

To solve the problem, to the NAT server, in a command prompt, enter:

netsh routing ip nat delete ftp

• Proposed as answer by Lythom57 Thursday, April 11, 2013 3:23 PM
• Edited by Lythom57 Thursday, April 11, 2013 3:24 PM

Worked for me. Thanks.

This worked.  It's better than disabling the whole firewall.