Linux command-view port occupancy

Common commands

• lsof -i:端口号
• netstat -tunlp|grep 端口号

lsof -i

• Used to show qualified progress

• lsof(list open files)Is a tool to list the open files of the current system
  

• lsofThe meaning of each column of output is:

  • COMMAND: The name of the process or the way the process was started
  • PID: Process id
  • USER: Process owner
  • FD: File descriptor
  • TYPE:agreement type
  • DEVICE:The port number
  • SIZE/OFF: Offset
  • NODE: Protocol name
  • NAME: Node name

netstat -tunlp

• Used to display tcp, udpport and process related information
  

• Command in the t, u, n, l, phave different meanings:

  • -t Only display related to tcp
  • -u Only display related to udp
  • -n Unlimited aliases, can display all the numbers converted to numbers
  • -l Only display those in the Listen state
  • -p Display the name of the program that established these connections

netstat -tunlp|grep port number

• Used to view the process of the specified port number
  • For example, check the situation of port 22:netstat -tunlp|grep 22