003_ Linux command summary


003_ Linux command summary


1th firewall

Firewall CMD command

  • firewall-cmd –list-ports
  • firewall-cmd –add-port=9092/tcp –permanent

    • –The permanent parameter must be added
  • man firewall-cmd

    • After opening a port number, you must reload it with reload, otherwise it will not take effect
  • firewall-cmd –reload
  • firewall-cmd –remove-port=9092/tcp

    • Close the port

2th netstat -lnpt

  • Ports 2181 and 9092 are occupied
  • Case,,, when zookeeper crashes, it is not easy to use the command to close zookeeper
  • This requires killing – 9 to end the process and netstat – lnpt to see the effect
  • You cannot view the effect without using the netstat – lnpt command, because zookeeper has crashed and the zookeeper command is not responding

The order is summarized as follows

netstat -lnpt | grep 2181

kill -9 2181

3th others

whereis java
whereis redis