In Linux machine sometimes we need to check what process that runs on certain port. We can use the following command to do that (ex. we want to check the process runs on port 1521) :
oracle@mytestbed:~$ lsof -i :1521 COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME oracle 2745 oracle 16u IPv4 245996 0t0 TCP mytestbed:1911->mytestbed:1521 (SYN_SENT) tnslsnr 2811 oracle 8u IPv4 233815 0t0 TCP *:1521 (LISTEN) oracle@mytestbed:~$
Alternatively we can use the following command :
oracle@mytestbed:~$ netstat -anp | grep 1521 (Not all processes could be identified, non-owned process info will not be shown, you would have to be root to see it all.) tcp 0 0 0.0.0.0:1521 0.0.0.0:* LISTEN 2811/tnslsnr oracle@mytestbed:~$