Everything:
sudo lsof -nP -iTCP -sTCP:LISTEN
For specific port:
sudo lsof -nP -i:[port-number]
fOr HaCkErS:
sudo nmap -n -PN -sT -sU -p- localhost
Source: https://phoenixnap.com/kb/linux-check-open-ports
Everything:
sudo lsof -nP -iTCP -sTCP:LISTEN
For specific port:
sudo lsof -nP -i:[port-number]
fOr HaCkErS:
sudo nmap -n -PN -sT -sU -p- localhost
Source: https://phoenixnap.com/kb/linux-check-open-ports