How to find the process listening on a given port
Use one of the following commands to resolve an open port to a running process.
How to use lsof
lsof -i :80
Alternative using netstat
netstat -tlnp | grep :80
Alternative using ssUsing ss has the advantage of given the full process name (not truncated like netstat) and also prints all PIDs having the port open, as lsof does.
ss -tlnp | grep :80