The ports to forward

[EmeraldStar82]

I have a ttt (gmod) server running on my laptop, I can't find what ports to forward, so many websites say so many ports.

My server worked fine until recently using the ports TCP and UDP 27015.
No one outside of my home network can join my server now >:(

I have tried also porting 27005 with TCP and UDP but that hasn't worked either. Can anyone tell me what ports are REQUIRED, I don't want to port forward more than I need to.

[blizz2208]

I run a css server i have 15 ports open from 27015 to 27030 But if you only run 1 server you should only open the 27015 TCP AND UDP that's what i do