Connectivity issues between friends

[Tomas]

Hello,

I and 4 other friends were comfortably playing Project Zomboid together through a server hosted in-game but suddenly we're all unable to play together now due to numerous issues such as:

• Initially, it started out as 2 friends got stuck in a complete black screen while joining the server, there is no text at the bottom.
  
• After a while, they were able to join with 200ms (before it was a smooth 20ms ~ 40ms) but it caused issues like zombies disappearing and teleporting.
  
• When in the server, some parts of the map do not load, it appears as the area is cut off and pitch black but we (the ones who don't have connectivity issues) can pass through.

We've tried a few things to fix the issue, here is what they are:

• We tried re-installing the game and deleting the Zomboid project.
  
• We tried changing saves and creating a new one but the existing issues were still present.
  
• I tried to host on Windows 10 and Debian 11, but the issues remained present.
  
• I also tried to host through in-game and a dedicated server on both operating systems.
  
• I tried reducing and increasing the server memory from 1GB up to 4GB.
  
• I tried hosting with and without UPnP, if without UPnP I would port forward.
  
• I tried hosting with DMZ enabled on my machine.

The host machine runs these hardware specifications:

• Ryzen 5 2400G.
  
• 16GB RAM.
  
• 120GB SATA SSD for the server and game.
  
• 300Mbps upload/download on fiber optic.
  
• Windows 10 Pro and Debian 11, both 64-bit.

The strange part is that this problem is only exclusive to Project Zomboid. I also run a Starbound dedicated server (both Windows and Linux) and everyone has no issues connecting, reportedly having the same ping when Project Zomboid wasn't acting up.



Any help is appreciated.

[Beard]

Try RAM up to 6GB, I also recommend restarting your Router as this seems like a connection issue.

[Tomas]

Originally posted by Beard:

Try RAM up to 6GB, I also recommend restarting your Router as this seems like a connection issue.

Unfortunately, bumping up the RAM to 6GB and restarting the router didn't change anything. I doubt it's a lack of memory, though, as the server was running just fine before with 1GB ~ 2GB RAM.

[Beard]

I would also suggest general network issues. It is very unlikely that the game itself is causing the lag if it is not a PC / RAM issue.
https://help.steampowered.com/en/faqs/view/669A-2F68-D1D1-A5EC

[Tomas]

Originally posted by Beard:

I would also suggest general network issues. It is very unlikely that the game itself is causing the lag if it is not a PC / RAM issue.
https://help.steampowered.com/en/faqs/view/669A-2F68-D1D1-A5EC

The strange part is that any other game we play has no issues whatsoever, I'm able to host and they are able to join without any issues, it seems that the connectivity issues is specific to Project Zomboid only for the meantime.

After we failed to play Project Zomboid, I was able to host and play Starbound with them (this was port forwarded using TCP which I also tried with Project Zomboid):
https://steamcommunity.com/sharedfiles/filedetails/?id=2720486480

Other games such as Killing Floor 2 (I also run a dedicated server for low ping) works flawlessly.

[Tomas]

Stumped. It seems like the issue isn't only related to me. A friend of mine tried to play PZ with another friend and was facing the same issues, long loading times, unusual 200ms (despite not having it in other games) and the world being unable to load.

[Beard]

Does the issue also happen on Public servers? The PZ server itself can put some strain on the PC if you are running the game at the same time, it is definitely way more demanding than Starbound could ever be, which could be the reason as to why it lags and other games dont.

[Tomas]

Originally posted by Beard:

Does the issue also happen on Public servers? The PZ server itself can put some strain on the PC if you are running the game at the same time, it is definitely way more demanding than Starbound could ever be, which could be the reason as to why it lags and other games dont.

Just tried to join a public server in my country just now. It works just fine and loads very fast with low ping (30ms). The problem is that my friends don't want to play on public servers since we only want to play co-op together (we use the listen server or in-game hosting to play together).

I also have a decent mid-range computer that's capable of hosting and playing games at the same time, I've been the person in the group that's responsible for hosting the games and I've been playing with my friends on the same machine for years and Project Zomboid, so far, is the only game to have this connectivity issue.

Starbound also is quite heavy to host especially with many people, I wouldn't say that it's heavier or lighter than Project Zomboid but they seem to be on-par together, though Starbound has a tendency to use more RAM (at one point when 5 of us were playing, the server alone managed to use up to 10GB RAM).

What I don't understand is that the problem suddenly appeared and still continues to this day, I kept hosting with the same settings (2GB RAM) and there were no issues until I got around 34 hours and up to this point we still are unable to play, some of my friends are able to connect while some are unable which is strange because one of the friends playing are from outside my country with 105 ms and they can connect just fine both in Project Zomboid and Starbound (or any other game). At first I thought this was caused by me changing from Windows 10 to Debian 11 but after switching back, the problem persisted.

It doesn't seem to be our ISP's routing at all since we're able to play other games together smoothly. I assume Project Zomboid is peer-to-peer, but other peer-to-peer games like Barotrauma also work just fine.

We can try again and provide logs (both on my end and their end) to see if a problem can be identified.

[Beard]

You could try but I found no errors in the log specifically, if it is a connection being slow or the world loading slowly then there will be nothing in the logs, because the server and the game itself works fine but it is external factors slowing down the game. Did you try creating a new server with at least 6GB minimum (2 is definitely not enough)?

[Tomas]

Originally posted by Beard:

You could try but I found no errors in the log specifically, if it is a connection being slow or the world loading slowly then there will be nothing in the logs, because the server and the game itself works fine but it is external factors slowing down the game. Did you try creating a new server with at least 6GB minimum (2 is definitely not enough)?

Yup, I have created a server with 6GB RAM allocated a while ago when you told me to and the same problems still occurred. I'm not sure if 2GB RAM isn't enough though because I've been hosting with that for weeks when we first bought Project Zomboid.

[Beard]

Hm, are you perhaps on a wifi connection or an ethernet connection? Recently there have been similar reports of bad lag by people who hosted on wifi connections, which is usually not recommended for hosting. Not sure what else to point to except the "general connection issue"
Since based on your explanation the game itself runs fine but just lags, which the server itself cannot do unless you are running a ton of mods, meaning it is caused by something external to the server, perhaps a bad connection or interference to the Steam servers, antivirus causing issues, internet service provider being problematic, router settings causing problems and so on.

[Tomas]

Originally posted by Beard:

Hm, are you perhaps on a wifi connection or an ethernet connection? Recently there have been similar reports of bad lag by people who hosted on wifi connections, which is usually not recommended for hosting. Not sure what else to point to except the "general connection issue"
Since based on your explanation the game itself runs fine but just lags, which the server itself cannot do unless you are running a ton of mods, meaning it is caused by something external to the server, perhaps a bad connection or interference to the Steam servers, antivirus causing issues, internet service provider being problematic, router settings causing problems and so on.

I'm connected to a 1000Mbps Ethernet connection on a 300Mbps Up/Down subscription. We use no mods at all and I don't have an antivirus nor firewall program (my Linux distro doesn't come with one) installed on my machine. It could be simply the ISP being awful at handling Project Zomboid specifically, but before the problem started there were no router settings changed. I also tried different ways to host the server:

• I tried hosting with the usual settings: UPnP enabled in the server settings and router.
  
• Next I tried without UPnP but have all ports forwarded, including the one where there is a 10 port range for the clients to join.
  
• I tried hosting with DMZ.
  
• I tried all the 3 things above, but with a dedicated server instead of a listen server.

The problem just occurred so sudden and still continues to this day (though it's not exclusive to me but also happens to another friend) and it's very specific to this game which is unusual. I assume it's probably just our ISP since there doesn't seem to be another good explanation for the problem.

**Edit:** I forgot to mention, I viewed the logs myself (both on my end and their end) and, unfortunately yes, there was nothing in the logs related to the issue. I miss PZ co-op.

[Tomas]

I forgot to provide context too on what ISP my friends are using.

Friend 1: From another country, can join just fine with 100ms but no issues.
Friend 2: Same ISP, can join just fine with 20ms and no issues.
Friend 3: Same ISP, can join but is severely slow, laggy with 200ms and have several issues like zombies teleporting and disappearing (also on my screen), and the world failing to load other parts.
Friend 4: Same ISP, can join but is severely slow like Friend 3.
Friend 5: Different ISP, unable to join at all now despite being able to join completely fine before the problem.

Any other games work just fine - the problem is exclusive to Project Zomboid. I will try out something though when they're available, I will change the ports the game uses and try hosting with UPnP, port forward and DMZ also.

[Tomas]

We've discovered something strange in the logs, this has been found in the coop-console.txt file.

We were able to play yesterday, the people with connectivity issues had higher ping around 150ms ~ 200ms, but then later the connectivity issues came back when the ping rose to 300ms and above.

This is the strange thing I've found in the logs:

LOG  : General     , 1643019731600> 10,773,035> User:'meiko' ip:143.42.143.67 is trying to connect
LOG  : General     , 1643021831938> 12,873,373> User:'meiko' ip:149.42.143.67 is trying to connect
LOG  : General     , 1643022488687> 13,530,122> User:'meiko' ip:149.42.143.67 is trying to connect
LOG  : General     , 1643023804478> 14,845,914> User:'meiko' ip:151.42.143.67 is trying to connect

For whatever reason, my friends who connect to the server are using the wrong IP address. This problem is also exclusive to Project Zomboid. Doing an IP address lookup on these IP addresses show that they are from:

• Philadelphia, Pennsylvania, USA
  
• Corning, New York, USA
  
• Piacenza, Emilia-Romagna, Italy

We're not sure if this is the cause of the high ping and connectivity issues but for whatever reason, Project Zomboid reports our IP addresses wrong. Is there some kind of relay process being done first before we're able to join?

[Tomas]

The problem has been solved, though I'm not sure what exactly solved it. We're now playing again with 2GB RAM allocated to the server and they're back to the usual 30ms ping.

The only thing that was changed in particular is the server is now hosted from the port range 7777 to 7787 and it's being hosted through port forwarding instead of UPnP with the game installed on a hard drive instead of the SSD.

¯\_(ツ)_/¯

[♿Eat.You.Alive♿]

hello did you figure out what the main issue ? Im having the same issue with my friends. Even tough we are in same city and same ISP when i try to join the server that my friend created the loadings and downloading the map is way too slow and after the while i finally join the game i struggle with 250-300 MS..