No ifconfig commands under Linux

You're not running this command with the root user, are you?
Try it this way:

Password: Enter the root user password
# ifconfig

It's still not there.

Use the Whereis command to look for:
# Whereis Ifconfig
If you can't find it, you may not have the system installed.

Whereis ifconfig -A

-B binary   search  only
-B (dirs) defines the binary file lookup path   
-M only manual search
-M (dirs) defines a person lookup Path
-S only source search  
-S (dirs) define source lookup path   
-F terminating ( directory ) parameter list    
-U unusual entry search  
-L Output a valid find path   

No ifconfig commands under Linux