Configuring The Router With Port Forwarding

To configure Serv-U to work with your router or firewall, you must first configure the router (and/or firewall) to forward your desired file transfer ports to the internal IP address of your server. While FTP is the most common one used, other protocols are also available in Serv-U 7+. These protocols and their ports are typically:

• FTP and Explicit SSL/TLS - 21/tcp
• FTPS (Implicit) - 990/tcp
• FTP-data 50000-50009/tcp
• SFTP - 22/tcp
• HTTP - 80/tcp
• HTTPS - 443/tcp

This allows the file transfer traffic to be routed through the router and directly to Serv-U. Routers typically call this option "Port Forwarding" - an example of how to forward ports in a LinkSys router is available at How To Configure A Linksys Router For Serv-U. Alternately, if your router supports Universal Plug and Play, Serv-U versions 6.2 and later can automatically configure your router through UPnP.

Configuring The Router With DMZ

In some cases, it may be preferable to forward all incoming connections to the server that is also hosting Serv-U. Most small routers also include the option to place a single computer in a "DMZ", or Demilitarized Zone, which sends all undesignated requests to a specific internal IP address. These include FTP/FTPS/SFTP/HTTP/HTTPS requests, but can potentially include harmful traffic from the internet as well. If the computer hosting Serv-U has known to be secure and is kept well-patched, the directions above on configuring a LinkSys router also include directions on configuring a DMZ.

Configuring FTP and FTPS in Serv-U

Once your router is forwarding the file transfer ports to your server, make sure that Serv-U is listening on the correct ports by checking in the Domain Details menu under the Listeners tab. If you are using FTP or FTPS, make sure to also configure the PASV port range in Serv-U using these steps, or by following this video.

• Navigate to "Server Limits and Settings | Settings"
  
• Enter the PASV port range in the Network Settings area (RhinoSoft.com recommends using the port range 50000-50004)
  

If you are still unable to connect, the next step is to configure the IP address Serv-U uses for its response to the PASV command so that it uses the actual IP address and not the internal IP that Serv-U sees. Serv-U 7.0 and above include the ability to specify a domain name instead of IP address. To do this, follow the steps below or follow this video.

• Navigate to Domain Details | Listeners
• Select your FTP/FTPS listener(s) and click Edit
• Enter the external IP address (or domain name if applicable) of your internet connection in the PASV IP Address Or Domain Name field. You can find this by surfing to www.whatismyip.com. If you are using Serv-U with a dynamic IP address, leave this field blank. An article with more detail about using Serv-U with a dynamic IP address can be found in our Knowledge Base.

  

If a this point you are still unable to connect, try disabling the "Block FTP_Bounce and FXP" option - this has been known to cause issues for some clients. To do this, follow the steps below:

• Navigate to Server Limits and Settings | FTP Settings
• Select Global Proprties. If this is not available, first select Use Custom Settings to gain access to it
• Navigate to the Advanced Options tab and make sure that "Block FTP_Bounce and FXP" option is unchecked (which it is by default)

Configuring SFTP, HTTP, HTTPS in Serv-U

To configure SFTP, HTTP, or HTTPS in Serv-U, first ensure that Serv-U is listening on the proper port by navigating to the Domain Details menu and opening the "Listeners" tab.

If you are using SFTP or HTTPS, ensure that you have configured Serv-U to accept encrypted connections using the instructions at KB Article 1053. If there is not an entry in Listeners that matches the protocol you wish to connect to, click "Add" and then add the listener (typically, the default port values are best).