E-Lab 5.1.4 - Configuration Register
In this lab, changing the boot procedure of the router will be examined.
Step 1
Start by entering into privileged EXEC mode.
Step 2
Examine the current configuration of the router.
The configuration register tells the router where to look for bootup information such as the IOS.
This can be done using the show version command.
Step 3
Examine the output and determine where the configuration register (the configuration register setting) is located.
Once it has been located, enter into global configuration mode.
Step 4
To change the configuration register information, use the command config-register.
The register is a 16-bit hexadecimal value.
Different values mean different things.
For example, a value of 0xnnn0 means to boot into the ROM monitor.
A value of 0xnnn2 to 0xnnnF means to use the boot system commands stored in NVRAM.
For this exercise, set the router to boot into ROM monitor mode with the hexadecimal string of 0x2100.
Since a boot into ROM monitor mode occurs before the full IOS software is loaded, only the most basic functionality will be available.