Pocketmine-mp: Some players cannot connect to the server.

[zKoz210]

Issue description

Hello, some of my players has a problem. They cannot connect to my server, or nothing doesn’t work.

Why I decided to create an issue? I tested the latest version of PocketMine-MP and Steadfast2. Therefore, if I am connecting to the server with Steadfast2, everything is OK, but on the server based on PocketMine, anything like a commands or chat are not working, and the chunks are not loading.

A video that shows the problem: deleted

PocketMine-MP: 19132
Steadfast2: 19140

Two servers are installed on my dedicated server (MC-32 OVH).

Steps to reproduce the issue

Unfortunately, I was not able to understand the cause of this problem..

OS and versions

• PocketMine-MP: https://github.com/pmmp/PocketMine-MP/commit/a4ca3f1d1c92d2e6238fb68400355d5fe7038345
• Steadfast2: https://github.com/Hydreon/Steadfast2/commit/42fd893194141f617827a5c584b207fd47e79ecd
• PHP: 7.2.0RC4
• Server OS: CentOS 7.4.1708
• Game version: PE/Win10

Plugins

• Game servers are tested without plugins.

Crashdump, backtrace or other files

I can send you any types of debug logs or something like that if you want.

[veme312]

I can confirm it

[dktapps]

my best guess is that it's something to do with Steadfast2's lower maximum MTU size... that's not really solving such problems, but it would probably mitigate it... try lowering this 1464 to 1432 or lower and see if it resolves your issue (https://github.com/pmmp/RakLib/blob/master/server/OfflineMessageHandler.php#L58)

[dktapps]

I've pushed a bugfix to RakLib for another MTU size bug, please test https://github.com/pmmp/RakLib/commit/9142e7decec23b302ab470a55e5ed160df4878db

[zKoz210]

The last fix works! Thank you very much! <3

[zKoz210]

@dktapps In some people the problem persists, I have to put 1432 everytime I update of pmmp.

This happens on very old routers, which are supplied as an additional service from provider.

[dktapps]

Yes, I experienced the same problem on an old library router. As I recall, manually lowering the router MTU size to 1432 helped alleviate the issue. I've been experiencing that problem since at least 0.15, with vanilla and PocketMine both.

[dktapps]

MCPE would often crash or fail to connect at all.