Answers for "how to check which process is using a port in linux"

linux query port use by pid

$ sudo netstat -nlp | grep :80
tcp  0  0  0.0.0.0:80  0.0.0.0:*  LISTEN  125004/nginx

ubuntu check process on port

sudo lsof -i:22

find out which procses is using port linux

sudo lsof -i:<port_number>

linux which process is using a port

$ sudo netstat -ltnp | grep ':80'

linux check what process is using port

$ netstat -ltnp | grep -w ':80'