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Where are these questions/answers from?
Originally some of the Q&A was collected from the old BitTorrent mailing list (which died in 2005) and some started here. However, the vast majority of the questions have been posed and answered directly on this wiki. Continue to do so! :)
NOTE: No one is in charge of the wiki content. The BitTorrent community is creating this FAQ. Big thanks to everyone in the community!!
Other FAQs and tutorials to check out: removed because they no longer exist
Wasn't there a list here of free BitTorrent sites?
Is there a bittorrent for FreeBSD, and how can I use it as a background process?
Yes, the BitTorrent client is available as a port (/usr/ports/net-p2p/py-bittorrent).
How can I use BitTorrent from a console or as a background task in Unix/BSD?
How can I create .torrent files using only the programs in the BitTorrent source distribution, without using a GUI?
The command line is "btmakemetafile.py blah.iso http://tracker.abc.xyz:6969/announce". Turns out the "/announce" MUST BE PRESENT in order for the resulting .torrent file to work correctly.
I download a file using bittorrent and it grows and grows. Now it is 10% bigger than it should be and it is still downloading. Is this behavior normal?
A : Yes it is.
A: Usually means you want a file the has very few or intermittent seeders and peers. You can end up waiting for hours or days for someone to come back online with the chuncks of the file you need to finish.
I want to leave running multiple torrents that I've already downloaded so others can download. However, I just want to run one copy of bittorrent so I can use a single --maxuploadrate command to cap the max amount of bandwidth used. Is there a way to do this?
A: [[BitTorrent-4.x]] does this without trouble. It has a slider at the top of the window that controls the total upload rate, too.
- Alternate Windows clients such as Torrentstorm have improved on the interface and give you both a per-torrent and a global upload limit, as well as a single GUI with progress for all torrents you are downloading/seeding. You can run multiple torrents on UNIX by using btlaunchmany/btlaunchmanycurses - unfortunatly the maxuploadrate is still per torrent and not global :(
How could I detect if BitTorrent is running on a host using HTTP headers? what would the HTTP query string look like?
A: The only thing BitTorrent uses HTTP for is the tracker. Use a URL like the "Announce" URL from a .torrent file to see if an HTTP site is running a tracker.
How can I determine my maximum upload bandwidth, so I can set the max to 75% of that?
A. Likely you're asking because of shared connection. Best method, Isp's have a link somewhere on their website to perform a bandwidth/speed test which takes less than a minute. Other method, search for 'speed test' careful not to download and install unnecessary software some try to trick you. Tests wont be very accurate if anyone else is busily using your connection at the moment.
Is there any way to cloak your IP address while using the torrent program?
A: No it's impossible, because clients connected to the torrent need to know the IP address of other peer clients to share and download parts of the torrent from.
Since IPs cannot be masked, for the sake of connected up/downloaders, how safe is this model? Are the users who are either uploading to you or downloading from you the only objects that can know your IP?
A: Trackers can report your IP even to people who are not downloading from you. Don't use BitTorrent if you don't want people to be able to see what you're downloading, since it is very public. In short, the tracker knows all peer IPs, and gives out a random subset of those to anyone who asks. Given several subsequent tracker requests, it is thus likely that a spying party may be able to retreive most or all of the active peer IPs.
Is there work going on to help BitTorrent be used for streaming media? I'm assuming it's not useful now because it doesn't try to get the beginning of the file first.
A: There already are several efforts underway in other projects, the most prominent being , , [[P2P-Radio|Streamerp2p], Skype and Joost . They use a similar idea to BitTorrent in that 'clients' can also become 'servers', but the model is different because the clients generally just help retransmit the feed they are receiving from an upstream server.
- BitTorrent's performance depends strongly on each client requesting 'different parts of the file from the seed. This gives each client something to trade with other clients (that they don't already have), making every client valuable to every other. Unfortunately, streaming has the opposite behavior: everyone wants the first part of the file first, etc. See Bram Cohen's article Bit Torrent Economics.
Is there any way to limit transfer rates/bandwidth
A: Yes, imagine that your connection to internet is like a unusual highway where the traffic travels very fast one way (download) and substantially slower the other way (upload). Every so often the client must tell the sender that it has received a good chunk of the file. If you have your upload speed set to the default of 0 which means unlimited and you are uploading at your max rate it will slow your download speed. Because the response to the sender for downloaded chunch is waiting on an upload chunck to finish. Family or friends sharing the connection will be affected by the client running unlimited up or down. Many clients have options to limit bandwidth.
If a torrent contains more than one file, is there a way to download only selected files?
Yes, most clients have this option, see the help file or author's website.
Is there a way... if the download is a movie... to cut the file... I really don't care to watch the last 2 minutes of the movie (the credits and so on). So the question is; Is there a way to cut the file at 97.6%, and watch it?
A: Note that BitTorrent divides a download into many pieces, and requests those pieces in any order, so the last 2.4% you download probably isn't from the end. Also important is that many types of video files just won't play if the end of the file is missing or truncated - the player sees them as damaged.
Why did all of the big search sites go down around June 1, 2003? Did hackers/virus/worm take down these search sites? Was it Aliens? Slashdot... again?
A: http://www.chillingeffects.org/ http://torrentfreak.com/ provide up to the minute information on the on-going battle between bittorrent users, trackers, and the Motion picture and recording industry.