Show Menu
Cheatography
  1. Home >
  2. Software >

RHEL9 Cheat Sheet (DRAFT) by

Cheat sheet for RHEL RHCSA Exam Study

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Minimum System Requir­ements

RAM
1GiB
Storage
10 GiB
Connec­tivity
Network Card
File System
XFS

Shell

Alias
 
alias newcmd­='o­ldcmd'
Internal commands
Part of the shell itself. Not loaded from disk.
External command
Exists as executable file on disk.
Locate command
 
which cmd
Run command in current dir
 
./cmd
$PATH
Variable of list where cmds are found
show $PATH contents
 
echo $PATH
 

I/O Redire­ction

STDIN
< or 0<
STDOUT
> or 1>
STDERR
2>
Write to file (initi­al/­ove­rwrite)
 
echo test > file.txt
Append to file
 
echo test2 >> file.txt
Send STDERR to STDOUT
 
ls badpath > file 2>&1
STDOUT to another command
 
ls list.txt | less
Hide STDERR but show contents
 
ls badpath 2> /dev/null
Hide STDERR but redirect contents
 
ls badpath 2> /dev/null > output