How to use UDP connections with Torrent clients?

Question

I just set up Ubuntu and I am having lots of trouble getting torrents working. I used to use Linux a lot, but have not for years, so I'm pretty new at this again.

I have ports forwarded on my router for UDP and torrents. I have checked them and they are open on the router, and using netstat I can see they are open/listening on the computer.

I did:

sudo iptables --flush and sudo ufw --disable to make sure that it was not a firewall causing the problems.

When I use http://checkmytorrentip.com/ It says UDP is disabled (it was working fine on my windows install). I can't connect to any trackers that are not HTTP.

I have tried qbittorrent, deluge, and transmission. None of them will connect to trackers using UDP.

I usually use a proxy (btguard) but I have that disabled while I just try an get the connection working period.

Any ideas as to what I am doing wrong?

Solution

A nice nmap scan shows that port 557 is closed in checkmytorrentip.com servers:

sudo nmap -p 557 -sU -P0 www.checkmytorrentip.com
[sudo] password for braiam: 

Starting Nmap 6.40 ( http://nmap.org ) at 2013-08-14 18:21 AST
Nmap scan report for www.checkmytorrentip.com (199.231.232.176)
Host is up (0.17s latency).
PORT    STATE  SERVICE
557/udp closed openvms-sysipc

Meaning, no matter what you do, it will remain like that. In deep scans, shows that none of their udp ports is opened:

sudo nmap -sU -P0 www.checkmytorrentip.com

Starting Nmap 6.40 ( http://nmap.org ) at 2013-08-14 18:22 AST

Nmap scan report for www.checkmytorrentip.com (199.231.232.176)
Host is up (0.12s latency).
Not shown: 998 open|filtered ports
PORT     STATE  SERVICE
53/udp   closed domain
5002/udp closed rfe

If you want to test against something, I recommend you to use tracker.publicbt.com:80 or tracker.openbittorrent.com:80:

sudo nmap -p 80 -sU -P0 tracker.publicbt.com
[sudo] password for braiam: 

Starting Nmap 6.40 ( http://nmap.org ) at 2013-08-14 18:24 AST
Nmap scan report for tracker.publicbt.com (31.172.124.2)
Host is up.
Other addresses for tracker.publicbt.com (not scanned): 31.172.124.3
rDNS record for 31.172.124.2: tracker.openbittorrent.com
PORT   STATE         SERVICE
80/udp open|filtered http

Comments

[user184159]

I have uninstalled Transmission because it was not what I want to use. I was just testing with it. I am just trying to get the trackers that are UDP to load. That is why I am trying to get this working.