Some common shortcut keys for Linux

To see if the port is enabled
telnet localhost 8888

Start a port, flat and pass the data through this port
nc-l localhost 9999 </etc/hosts
View
Ss-anput | grep 9999

To see which process the device is using
Lsof-/DEV/SDB1

Common shortcut keys
Ctrl+l = Clear
CTRL + A
Ctrl+e
Ctrl+w = entire row deleted
Ctrl+r = history
!cat performing the Last Cat command
！ The first few commands of the digital execution history

^ Previous command ^ command executed this time
^vim^cat

View current directory Size
Du-sh

Df
View disk space size

Close a port
Find PID
Netstat-anput | grep 8888
kill-9 [PID]

View Memory
Free-m

Do aliases
Alias logstash-plugin= '/opt/logstash/bin/ogstash-plugin '

Telnet command
Telnet <ip> <port>
User <username>
Pass <password>
List
RETR 1
Quit

Some common shortcut keys for Linux