Re: [Hampshire] using wu-ftp

> I didn't think anything explicitly used port 20 any more.
> Most I've used just open an arbitrary port and use that...

It depends on how the server is set up...

The port 20 thing is PORT mode; the client connects to port 21, and then
the server connects from port 20 to the port one higher than the client
used originally. This doesn't go through typical NAT router configurations
very well...

So most FTP servers use PASV mode these days - in this, the client
connects to port 21, and is given a port number to which to connect. The
client then connects to that port - so the onus is on the server to make
sure that port is open on the firewall.

Most FTP servers allow you to specify the port range that will be used for
the PASV connection, so you can open a range on the firewall & use them
for FTP.

Vic.