A torrent is identified by its "infohash", a unique number derived from the files it contains. Magnet links and DHS use this to find seeds and peers.
However, the trackers, and the comments are not included in the hash calculation so you can change those and still have the same torrent; i.e., all those seeding the old torrent will be found by anyone getting the new one, differing only in its trackers.
You might want to do this if you have a torrent found at another site, may be several years old but still seeded, but most of the trackers are dead. Or one you made some time ago.
(See our
current list of trackers here.)
You can do this using a torrent editor such as
Torrent File Editor.
Opening an old torrent with this, I see:
Note the infohash:
c2bfd0deacae253f533e0cfbaef44af0230a671f
Now I edit the trackers list, the comment, and change the creation date:
Infohash is unchanged. (I jot down the last 4 characters when I open it and double check these are the same before I save.)
If you change anything else, such as the "Name", the hash will change and you have a new torrent, and have no connection to old seeds. Same goes for the "Private" flag, which disables DHT. Changing that will change the hash. You can't set the hash directly, it is calculated from the other data.
Upload this torrent and peers will connect with any seeds of the 2009 torrent.
TFE can do a lot of other things, including creating new torrents or checking out weird ones, if you're interested.
