What Happens As Your Router Boots Up
1. The “Power-On Self-Test” checks the Router Hardware.
This includes the CPU (Central Processor Unit), memory, and interfaces.
2. The “Bootstrap Program”, which is stored in ROM, runs itself
3. The “Bootfield” is read to find out the proper Operating System source.
4. The “Operating System Image” is loaded into RAM. (Random Access Memory)
5. The “Configuration File” saved in NVRAM is loaded into the RAM.
The Configuration File is then executed one line at a time.
6. If no “Configuration File” is found in NVRAM,
the Cisco IOS will offer you the chance to use the “Initial Configuration Dialog”.
This is a set of Questions for you to answer to do a basic configuration.
Since in our theoretical New Router there is no NVRAM configuration
This “Setup Dialog” will be one of the first things we see.