ftp server behind NAT

bax · 03-02-2003, 10:52 PM

Does anybody have any suggestions on setting up a publicly accessible Linux based FTP server from behind a router w/ a static IP running NAT? I am planning to use Redhat 8x but I'm open to suggestions.

bbenz3 · 03-03-2003, 12:29 AM

what kind of nat server do you have running. I am running a linux firewall/router box for my inet access. I am using an iptables script and in order to make it work just pick some random port number that isn't normally in use ie something kind of high and then you just setup a rule that forwards all traffic going to that port to your internal computer's IP addy on port 21. If you are running an iptables script I can help you out really quickly. Otherwise it will take a little thinking and a little more info on your setup.

bax · 03-03-2003, 07:58 AM

I don't know what model but I htink it's just a Linksys.

Crashed_Again · 03-03-2003, 09:10 AM

You should be able to configure your Linksys router to do port forwarding. As bbenz3 said you can tell the router to forward all requests it gets for port 21(FTP) to the port that you have assigned FTP to on your machine. You can specify what port you want FTP to run on your machine but the default is 21. In this case you would just have the router forward all requests from port 21 to port 21 on your machine.

bax · 03-04-2003, 08:45 PM

Cool, sounds like I'll either have to have the ftp box send its hostname to the router or give the ftp box a static IP, right?
Any recommendations on which software packages to use?

wind · 03-04-2003, 08:50 PM

i suggest you could use the proftpd server + iptables (NAT)

perhaps you should try it for some times

bbenz3 · 03-04-2003, 09:41 PM

The Linksys should give out IPs automatically and if it is like most DHCP servers it won't assign the IP to another computer till it has used all the available IPs, so you shouldn't to worry about trying to make it static. All you need to do is figure out how to access your Linksys router's config page and setup the port forwarding part to go the IP of your ftp server. Then on your ftp server you have to have the actual ftp server app running to host the server and that should be it, besides setting up the actual accounts.