Gosh ! I'm a genius !
- Working on a Sysadmin school project
- configuring the firewall
- looking myself out
- beg my teacher for reinstall
Fml right now ...

Could use a rescue disk then manually edit the iptables file

Yep, but we are working on OVH VPS so we don't have physical access and only the teacher has the access to reboot/reinstall.
In my case, only a reboot is necessary since iptables configuration is not persistant when you just type them in command line (was testing some rules)

Thanks for the advice, I'll search in that direction when I'll get my own server !

I thought about doing that on my testing server while I'm working on firewalling