[Server] UDP Initialization failed

[Xelfi]

Hello,

I'm currently studying in Ireland (I come from France) and I've a problem on Trackmania² Stadium:
When i try to join an online server, i often get an error : "Connection Failure : UDP Initialization failed".
As I am on my college connection, i thought it was due do it (and i think it mainly is)
But i've this error on most of the server, but not all ! I can join some server.

I've conclude that if I can join some servers, this problem can be fixed server side (i can not fix my connection because it isn't mine)
So I've decided to create my own server (hosted on an OVH server) in order to have a server that my friend and I can join when we are connected onthe college wifi. But I've the same problème "UDP Initialization failed" and I don't know how to fix it, some ideas ?

PS: My server is open and i can connect to it and play with my 4G (But I dont want to use my 4G to play trackmania, the connection is bad, and i don't have a lot of)

Sorry for my english :/

[oliverde8]

If I am remember right, the UDP connection is only used for the p2p; file sharing between players and the dedicated.
Basically it's used to share car skins & custom assets.

So even without changing anything on the server in your game settings (Launcher > Settings) in the P2P tab disable it. You shouldn't have problem with any server now (crossing fingers)

[Xelfi]

Thanks for your answer !

In Launcher > Settings, I've unchecked all the boxes in the P2P TAB : https://i.imgur.com/wGjN2tW.png (Sorry it's in french)
I've also disable all game settings related to vehicles skins.

But i still get the same error :/

Maybe i should try disabling P2P on the server ? (I'll try right now but I dont know how to do it)

EDIT :
I deactivate p2p in serversettings:
<enable_p2p_upload>False</enable_p2p_upload>
<enable_p2p_download>False</enable_p2p_download>

Still get the same error, any ideas ?

[jonthekiller]

UDP is now used for everything, it's mandatory.

If you are on a managed network, it's maybe blocked (like other stuff) for security. Maybe the network block only some ports (a Wireshark study is needed to see it).

If you can connect through a 4G connection for example, you can be sure that it's a network limitation.

[Xelfi]

Oh but I'm sure that it's a network limitation, but like I said before, i can join some servers.
So even if it's a network limitation, it can be fixed server side tho.

Maybe i've to find which UDP ports are open with Wireshark and modify it on the Launcher -> Network : https://i.imgur.com/enpR1Qt.png
I don't event know what to do

[jonthekiller]

For me it's the port used by the server (2350 by default).

[Xelfi]

For me too but it doesn't work :/

I've an UDP error but not with every servers

[Xelfi]

To sum up:

I'd like to join my server with my college's wifi (I'm living there) buy I got an error : "UDP Initialization failed" (other students have the same error)
But I can join some other online servers (not all) and I'd like to know how avoid having this UDP error

I think it have to be fixed server side, but I don't know how

[oliverde8]

Did you try changing the ports on the server. Try 2360 instead of 2350 and 3460 instead of the 3450 for example.
Using wireshark you can pinpoint what's not working and what's is working. But it if you have never used it before it can be intimidating.

Another possibility is to try a VPN, It will add some Ping but should allow you to bypass the issue if the VPN's are not blocked.

[Xelfi]

Thank you for your answer,

I've already tried 2352 and 3452.
And I had never tried Wireshark before yesterday, and yes it's a bit intimidating but I've understood how it's works (I think )
But I dont really know what do to with it, the ports 2350 and 3450 are open on my server. But for the college's wifi, it's seems to be a lot more confusing I dont really know what is open (My school is probably using a proxy, so I've an internal IP (which i can get with ipconfig) and an other IP when i'm on internet (wich i can get on whatismyip.com for example).

VPN can be a good solution but this is not free, and i'd also like my friends living in the same campus to join the server. Moreover, I can join some other trackmania servers, without using a VPN or something else.

It seems that my connection is a bit "weird" cause it's a "public" connection and that trackmania servers are blocking that by default :/

The main point is that i'm allowed to join some servers, but not all due to this UDP error