check process port centos code example
Example 1: 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
Example 2: find out which procses is using port linux
sudo lsof -i:<port_number>
$ sudo netstat -nlp | grep :80
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 125004/nginx
sudo lsof -i:<port_number>