AlternateMasterSupport (or AMS for short) is a third-party master server implementation for Tribes 2. It doesn't use the same protocol as the official servers, so it can be implemented in Tribes 2's scripting language and used when the client is in "Local" mode. The server list is shared with krash123's microTCMS.
In short, you want AlternateMasterSupport so that you can continue playing Tribes 2. If you're here because you can't log in to Tribes 2, you've come to the right place.
Sierra/Vivendi/Blizzard/Activision announced that, as a result of "recent corporate acquisitions and mergers," the Tribes 2 "game servers" would be shut down on November 1, 2008. The servers finally died on Monday, November 3. Since the authentication servers were shut down, it's no longer possible to log in to Tribes 2 to play online — your only option is to play on a LAN server with friends/bots or to play on servers that accept connections from anyone when running as a dedicated LAN server.
AlternateMasterSupport will query an independently-run master server for a game server list, allowing you to find servers to play on using the in-game browser — even when running in local mode. After installing the script, the servers listed at the bottom of the page will appear in the game.
First and foremost, I really don't want to see Tribes 2 die. Although some others are currently working on different solutions to the problem (see discussions in the Sierra shutting down master servers thread on the-construct.net), we needed a solution we could start telling people to download immediately.
The game itself was the only common means of communication that all Tribes 2 players had, and now that the official servers have gone dark, some players have probably been lost forever. Still, it appears that enough players have heard or figured out what's going on, and with luck the community will survive (and perhaps grow, since there are no more CD keys to check.)
I believe it's important not to fragment the user base across a half-dozen reimplementations of the master servers. I put some effort into making sure AlternateMasterSupport won't interfere with other peoples' work (it peacefully coexists with the in-game browser, even in online mode) and I'm interested in combining server lists with other projects. I intend to keep this master server alive for as long as people are using it.
If we keep the game alive, I'd love to look into reimplementing an authentication system and reviving the IRC client, TMail, and the browser. Obviously, the current database will be lost when the official servers are shut down, but I believe that most or all of the other functionality can be brought back in the local client.
Clients only need to download the script to query the new master server. This script is just like any other script addon for Tribes 2: download AlternateMasterSupport.vl2 and put it in your Tribes 2 base directory (e.g. C:\Dynamix\Tribes 2\GameData\base). Once you've installed the script, the alternate master will automatically be queried whenever the game refreshes its server list — just start the client in LAN mode and the rest should come naturally. This script does not interfere with LAN play, and LAN servers will still appear in the server list alongside the Internet servers.
Servers need AlternateMasterSupport.vl2 just as the clients do, plus one extra step. When a server is running in LAN mode, it places restrictions where other clients can connect from (in an attempt to keep the game confined to the local LAN.) Since it's no longer possible to run servers in online mode now that the master servers have been shut down, server administrators will need to overcome this restriction to allow the Internet at large to connect to their servers.
I have created a very simple patch to disable this check on both Win32 and Linux servers running version 25034. If you use a hosting provider your server and you can't run anything on the server host, you can apply the patch locally and upload the resulting server executable. If you do not plan to run a Tribes 2 server, you do not need this patch -- only the .vl2 file.
To run your server in LAN mode, remove -online from the server command line (if present) and add -nologin. Please note that, at least initially, all of your clients will be smurfs. You may need to update your server configuration to allow smurfs to connect, and you may need to implement IP banning.
Download the LAN fix for Win32 servers and extract it in your Tribes 2 GameData directory (e.g. C:\Dynamix\Tribes 2\GameData), then run tribes2-lan-fix.bat. If it runs successfully, it should display no errors and create a new executable called Tribes 2d.exe. You can either use the new executable directly or back up your original Tribes 2.exe and overwrite it.
Download the LAN fix for Linux servers and extract it in your Tribes 2 directory (e.g. /usr/local/games/tribes2), then run tribes2-lan-fix.sh. If it runs successfully, it should display no errors and create a new executable called tribes2d-lan.dynamic. You can either use the new executable directly or back up your original tribes2d.dynamic and overwrite it.
If you find a problem with the script or the master server, please let me know. I can be reached via electronic mail by putting together t2ams, an at sign, and the domain name of this site (plugh.us) (update: now with more workage.) I also play the game as Rain or Raineth.