For windows;
Where can we change the port numbers?
We need a change the sftp port number.
Serv-U port numbers are defined in each domain's listeners (not by global parameters). Drill down to your domain first (it might be your only domain), and then open up your listeners. At least one will be for SFTP/SSH - change it. (You may have multiple SFTP/SSH entries if you are listening on multiple ports OR if you have Serv-U Gateway installed since that requires separate listeners for Serv-U and Serv-U Gateway.)
As a rule, I recommend that you ALWAYS use a port other than 22 for your Serv-U SFTP traffic because an Internet-exposed port 22 will be scanned continuously by script kiddies looking for access to *nix boxes. Instead, use (firewall- or router-based) port forwarding or adjust the listener (as described above) to move Serv-U's SFTP/SSH to something like 2222.
-- Jonathan Lampe, CFTP, CISSP -- File Transfer Consulting, LLC
"Are you a Certified File Transfer Professional (CFTP) yet?"
It sounds like a combination of good advice and security-through-obscurity, which might be negated with a port scan by those script kiddies looking for open ports.
In that kind of environment, I've recommendations for putting ACLs on all equipment to define a specific host, or small number of hosts, from which management access (like SSH) is allowed.
It narrows the chances of an unauthorized person being able to discover and access listening ports like SSH's TCP 22.
