Documentation for PROXY protocol is missing

[jemand771]

While searching for a way to forward the client IP I found #22 (issue: #13) which has already been released, but the README doesn't contain any info about it.
First of all, the usage code block would need something like this:

  -use-proxy-protocol
        Send PROXY protocol to backend servers (env USE_PROXY_PROTOCOL)

And maybe some additional info on configuring the actual minecraft servers to accept the proxy protocol.
(I realize that this might be vastly different between server "flavors", but at least a general hint in the right direction would be helpful anyway)
The way I have it now, I can't connect to a fabric 1.18.1 server behind mc-router when I enable the proxy protocol, but this might be a config error.

[itzg]

cc @Gabitzuu

[Gabitzuu]

Hi. Yes, I forgot to add the README part regarding PROXY protocol.
Basically, your server has to accept this protocol, either by itself (eg. Bungeecord/Waterfall/Velocity *iirc), or by using a plugin (SpigotProxy/FabricProxy-Lite)
Sadly, I'm not familiarized with Fabric, so I can't really help you, but this might help: https://www.curseforge.com/minecraft/mc-mods/fabricproxy-lite

[jemand771]

thanks for the quick reply, I'll have to play around with this a bit more. So far I couldn't get it working at all (even with spigot/paper) but I didn't spend much time troubleshooting yet.

Does mc-router implement the "new" (often called "modern") or the legacy forwarding? Most plugins/mods let you configure which one to use (and I should probably pick the right one)

[itzg]

@jemand771 it's currently PROXY v2, but I vaguely remember what you mean about some alternate client IP forwarding protocols for Bungee type scenarios. So it might turn out the particular support you're needing isn't here yet.

[itzg]

Hmm, the ip_forward feature seems to work by encoding it into the host field of the handshake. That would be doable here in mc-router

https://github.com/SpigotMC/BungeeCord/blob/9c95d4ba43ba84d10e8bb7d7c92d7e6c5f161ed2/proxy/src/main/java/net/md_5/bungee/ServerConnector.java#L108