Find the process listening on some port on Linux

• 1 sudo netstat -tulpn # All listening
  sudo watch ss -tulpn # Realtime
  sudo lsof -i :PORT_NUMBER
  
• 2 Process info:
  sudo ps -ef --forest | grep PROCESS_NAME
  sudo ps -f --forest -C PROCESS_NAME
  
• N Monitor running processes with top, iotop, htop or glances
  

References

• https://ostechnix.com/how-to-find-which-service-is-listening-on-a-particular-port/
• https://www.tecmint.com/ps-command-examples-for-linux-process-monitoring/
• https://www.tecmint.com/watch-tcp-and-udp-ports-in-linux/