From their Website
No More Room in Hell is the ultimate ruthless and unforgiving co-operative zombie survival experience on the Source Engine, delivering award winning survival horror gameplay with dozens of weapons and multiple game modes.
NMRIH servers require 1 port to be open, the SourceTV port can also be opened for spectators.
| Port | default |
|---|---|
| Game/rcon | 27015 |
| SourceTV | 27020 |