So this is a bit of a weird one, but a potentially a serious issue for my server. I’ve been running custom modded forge servers for nearly 4 years now, on the same machine and been using Sponge since beginning of last year; however I have never come across an issue like this and I’m at a loss at what to try next.
I recently reset one of my servers and updated it from 1.10.2 to 1.12.2, using all the latest versions of mods, SpongeForge and Forge. At the moment I have it whitelisted so only the staff can join, and immediately we noticed that if there is someone online and one of my US based staff try to join, they get intense connection lag and then time out within a couple of minutes. For context, the server is hosted in Norway and I am in the UK with no connection issues at all. However, if no one else is online, they can play absolutely fine. I also host another 1.12.2 server on the same machine and they have no problems with that one (Although it is a bit behind in Forge and SpongeForge versions).
One of the first things I tried to do to trouble shoot was remove Sponge (and all the plugins), however that just made things worse - the server just lagged like someone dropped a billion entities, making it unplayable even for me. So I tried adding SpongeForge back, but kept the plugins out. It worked fine for me, but not for them; same problem as originally stated. So I stripped down the mods from the server so only the mods which added actual items remained; same result as before.
Next step really would be to continue to strip the modpack down, however that could take all night and my US staff are currently unavailable.
Anyway, the point in this post is that I’m asking you all, as server owners, have you ever came across this problem in the past, and if so, what did you find that caused it? I just need somewhere to look from here.
This server is supposed to go live tomorrow - I’m expecting 50-200 players to join within the first few days and a lot of those will be from the Americas; hence my desparate post here
Many thanks for any suggestions, input or comments.