IMPORTANT LINUX COMMANDS:-

# Check network connectivity. Ping the IP Address
$ ping 1.2.3.4 

#Check SSH service is up and running.
$ systemctl status sshd

# Check if the software is available in Red-hat.
$rpm -q docker

PS COMMAND:

# PS command to get top process consuming memory
$ ps auxf | sort -nr -k 4

# PS command to get 5 top process consuming memory
$ ps auxf | sort -nr -k 4 | head -5
 
# PS command to get top process consuming cpu.
$ ps auxf | sort -nr -k 3

# PS command to get top 5 process consuming cpu.
$ ps auxf | sort -nr -k 3 | head -5

FIND COMMAND:

# Search the current directory for all files larger than 100MB
find. -type f -size 100M