Low max player count Call of Duty 2 server
With the Corona virus being out I just got a lot more time on my hand. Decided to finally finish my little mod and make a permanent COD2 server. However, only 12-13 players can play at the same time. When more players connect they have a ping of 999. Someone with COD2 server hosting experience has an idea whats going on?
I'm running a dedicated COD2 1.3 server and Voron's libcod builded against the latest source. It's running only 1 additional custom map and 1 small mod I wrote myself. The server is a virtual machine running on ESXi 6.7 and has 4 GB RAM allocated and plenty of storage left. CPU usage is only 10%, network usage around 2 mbps avarage, and almost no disk activity when 12-13 players are playing. The server is behind an enterprise firewall / router that served 100 concurrent connections with no hiccups in the past, and should easily do a multitude of that on paper. The internet connection is a 500/500 mbps connection and the COD2 server has its own IP address. The hardware firewall is not limiting connections. The software firewall on Ubuntu (UFW) is a standard configuration with a few alterations (allow outcoming, deny incoming except the COD server ports).
Is there some ESXi or Ubuntu (UFW) setting that I'm missing? Is it possible my ISP is limiting incoming connections per IP? Anyone knows a tool to test this without needing to find >12 clients on different network locations?