Active ports on your system

Usage

• To check active ports on a system we use netstat command.

• To check active TCP ports.

  $netstat -tnlp
  

• To check active UDP ports.

  netstat -unlp
  

• Further if you want to check kernel’s routing table.

  netstat -r
  

• To view active interfaces.

  netstat -i
  

Flags

Flag	Description
-t	tcp
-u	udp
-l	listing
-p	process id and process name
-n	nolookup (it shows IP rather than HostName)
-r	routing table
-i	interfaces