Help: Torrent dowload question

[DarrylR]

All,

I need some general advice on downloading torrent files. I have tried
unsuccessfully to download torrents from mininova.org with a variety of
clients, including Bittorrent, Utorrent, and Azureus. After reading the
available documentation on each client and googling for tips, I opened what
I thought were the correct ports on my ISA (Internet Security and
Acceleration) Server 2000 firewall (a software-based firewall from
Microsoft). However, my downloads never actually retrieve any content; after
letting one run for 12 hours yesterday, it was still at 0%, and the log
contained only "unexpected end of file" and "connection reset by peer" error
messages.

One of the torrents in question has been downloaded over 3,300 times, and it
has 181 seeds, so I don't think it's a problem with the torrent. I'm
beginning to think that it's a problem with the port range that I'm using.
The Azureus documenation suggests that you only need to open a single port
(hard to believe, but if anyone can tell me the exact port, I'll be
greatful). Their guide mentions 6881, but I discovered by googling that many
ports in th 6800 range are blocked by ISPs because of their usage by P2P
programs. The other clients suggested port ranges, although I couldn't find
any definitive documentation on the exact ports. I opened the following port
combinations (and identified 50361 as the listening port in all 3 clients
that I tried):

Primary: 6880 TCP Outbound (because the Azureus NAT test utility mentioned
that 6880 was used internally)
Secondary: 1-65535 TCP Inbound

Primary: 6880 TCP Inbound
Secondary: 1-65535 TCP Outbound

Primary: 50361 TCP Outbound
Secondary: 1-65535 TCP Inbound

Primary: 50361 TCP Inbound
Secondary: 1-65535 TCP Outbound

Primary: 50361 UDP Send Receive
Secondary: 1-65535 UDP Receive Send

Primary: 50361 UDP Receive Send
Secondary: 1-65535 UDP Send Receive

Although I don't have any files to serve up or seed (yet), I also created a
server publishing rule that forwards ports 6880 and 50361 so that my machine
can serve content. Azureus verified that 50361 is forwarded correctly, but
it does have a warning about DHT being firewalled.

The URL of one of the torrents that I'm trying to download includes port
6500 (http://tracker.<snipped>:6500/announce). Would I need to open port
6500 to access this torrent?

Any advice will be greatly appreciated.

Thanks,
Darryl R.

[Hop-Frog]

Post by DarrylR
I need some general advice on downloading torrent files.

Then the discussion should be in alt.bittorrent. I've set the Follow-up
To: header.

Post by DarrylR
However, my downloads never actually
retrieve any content; after letting one run for 12 hours yesterday, it
was still at 0%, and the log contained only "unexpected end of file"
and "connection reset by peer" error messages.

I'd guess from the information you give here and elsewhere in the post
that the particular torrents you're trying to download require logging in
to the tracking website. Many of the torrents listed on Mininova are
actually tracked elsewhere, and some sites require that your IP also be
logged in to their website in order to join the swarm. This is to ensure
that everyone who downloads also uploads. Try entering the server name
listed in the torrent Announce URL (without the :6500/announce) into
your web browser, and it will probably redirect to a website with more
information about the torrents and how to get them.

Post by DarrylR
The Azureus documenation suggests that you only
need to open a single port (hard to believe, but if anyone can tell me
the exact port, I'll be greatful).

Correct. Azureus only needs one "listening port" opened in the firewall
or forwarded in the router. Most modern BitTorrent clients require only
one port; older clients need(-ed) one port for each active torrent.

BitTorrent clients make three kinds of connections: (1) outgoing HTTP
connections to the tracker. These are the same sorts of communications
your web browser uses, and are made on the port specified in the Announce
URL. (2) outgoing BT connections to peers. These are made on random
ports as needed. You don't need to configure either of these types of
connections in your firewall/router; since they're outgoing, just give
the application permission to access the internet. (With Azureus, that's
javaw.exe, not Azureus.exe.) (3) incoming connections on the "listen
port." These are connections initiated by other peers. *They* "dial"
*you*. These connections need to be configured in the firewall, because
the system has no way of knowing which application they're destined for
until the connection is accepted. You choose exactly which port in the
BT client's configuration; any port number will do, but a high number in
the 54000's or so is recommended because those ports are not assigned to
other internet applications.

Post by DarrylR
Their guide mentions 6881, but I
discovered by googling that many ports in th 6800 range are blocked by
ISPs because of their usage by P2P programs.

Correct. By some estimates, BT traffic now makes up 80% of all internet
traffic. (Seems a bit high to me, but who knows?) All BT clients will
default to using 6881 as their listen port--that was just a quasi-random
number chosen by the original developer--but that should be changed
A.S.A.P.

Post by DarrylR
Although I don't have any files to serve up or seed (yet), I also
created a server publishing rule that forwards ports 6880 and 50361 so
that my machine can serve content. Azureus verified that 50361 is
forwarded correctly, but it does have a warning about DHT being
firewalled.

Azureus uses a "Distributed Hash Table," a system that makes the
dedicated tracking server (in the Announce URL) unnecessary. It trades
tracking information with other DHT clients on the UDP port with the same
number as the TCP listen port. You'll usually need to create two
separate forward/exception rules for the same number: one TCP, one UDP.

Post by DarrylR
The URL of one of the torrents that I'm trying to download includes
port 6500 (http://tracker.<snipped>:6500/announce). Would I need to
open port 6500 to access this torrent?

This, as I've alluded to, is the Announce URL. When the torrent is first
loaded, the client creates an outbound HTTP connection to "tracker.
<snipped>" on TCP port 6500, and requests the list of active IPs. The
tracker tells the client who's in the swarm, and then the client contacts
each of them, trying to establish a connection and get some data.
Periodically, the client goes back to that tracker to report some
statistics and grab newly joined IPs. Since this is only outbound
traffic, you don't need to open 6500. Most trackers will use different
ports, anyway. The default is 6969, but that has been used by some
worms, so it is occassionally blocked by web hosters.

Post by DarrylR
Any advice will be greatly appreciated.

If you still have questions, be sure to ask in alt.bittorrent. There are
many of us over there who're more than willing to help.

[DarrylR]

Wow, after a couple of weeks of banging my head against the wall, I finally
found a way to make Bittorrent work. I had to configure the range of ports
that it was using from the command line. Once I opened port 6500 for TCP
Outbound and limited Bittorrent's range to the port that I had opened (50361
to 50361) using the instructions found here:
http://dessent.net/btfaq/#wincmdline, it begain downloading and uploading
correctly. I'm not sure whether opening port 6500 contributed to the
solution, but I'll wait until this file is completely downloaded before
modifying the settings.

Regards,
Darryl R.

"DarrylR" <***@nospam.com> wrote in message news:moWdnTp3b6X7M2_eRVn-***@comcast.com...
<snip>

Post by DarrylR
I opened the following port
combinations (and identified 50361 as the listening port in all 3 clients
Primary: 6880 TCP Outbound (because the Azureus NAT test utility mentioned
that 6880 was used internally)
Secondary: 1-65535 TCP Inbound
Primary: 6880 TCP Inbound
Secondary: 1-65535 TCP Outbound
Primary: 50361 TCP Outbound
Secondary: 1-65535 TCP Inbound
Primary: 50361 TCP Inbound
Secondary: 1-65535 TCP Outbound
Primary: 50361 UDP Send Receive
Secondary: 1-65535 UDP Receive Send
Primary: 50361 UDP Receive Send
Secondary: 1-65535 UDP Send Receive
Although I don't have any files to serve up or seed (yet), I also created a
server publishing rule that forwards ports 6880 and 50361 so that my machine
can serve content. Azureus verified that 50361 is forwarded correctly, but
it does have a warning about DHT being firewalled.
The URL of one of the torrents that I'm trying to download includes port
6500 (http://tracker.<snipped>:6500/announce). Would I need to open port
6500 to access this torrent?
Any advice will be greatly appreciated.
Thanks,
Darryl R.