What should I do when someone is trying to crash my server?

I just open my server and some guy was trying to crash it

How exactly? He DDoS your server, spawn a lot props? Send more information 'cause i don't know how to help you

most of the things that crash your server you can see in the console and then you can just restrict the tools and props or put in an safety tool

I would recommending giving them a warning or a temp ban for a few days, if they come back and continue i would ban them permanently as they arnt there to play the server, they are only their to ruin the server.

Shout something or warn them then if not kick them or just find new server

Just outright ban them tbh. People who do this type of thing won't have a change of heart overnight.

just ban their entire IP if you can find that out or something, idk.

just ban their entire IP if you can find that out or something, idk.

I'd ask him why, and then give him time to explain while he was frozen, and then ban him permanent xD

Prop protection so that people cant crash the server with props, anti cheat so people cant flood lua errors, etc.