Cisco Router Boot Sequence
Here we’re likely to go over from a high amount of how a Cisco Router boots once you turn the power switch to on which is going to help you in your CCNA studies. For the most part, the first boot procedure is controlled from the BootROM which permanently stores the startup diagnostic code(ROM Monitor). The most important job of this BootROM would be to operate the Power On Self Test (POST), that would be the hardware diagnostics and also to load the Cisco IOS software in the Flash (in most instances ) to memorycard. Be aware that the Boot ROM isn’t erasable.Visit here https://www.examreactor.com/
1. The BootROM will initialize the hardware and run via the POST to be certain that there aren’t any hardware mistakes and also the CPU and ports are fully working. If There’s Some Kind of mistake, you may see it at the POST since the router begins to boot up
2. Next the BootROM finds and loads a valid Cisco IOS image. Below You’ll Find the procedure that the router goes through to load the IOS image:
The router checks the Flash to get a legitimate IOS.
When there is not located in Flash and it has a different Boot-Helper picture, it may load the IOS through a TFTP host (netboot)
Eventually, as a last resort it’ll load the RxBoot mini-IOS that’s located in ROM.
3. The router then checks the Configuration Register value (NVRAM) to determine where to load the router setup file from. By default that is stored on an EPROM called startup-config that does not lose its contents once the router is powered off. If a legitimate startup-config document can’t be found, the router will automatically load the System Configuration Dialog, which essentially drops you into Setup mode. Then you’ll have the ability to carry out the initial setup of this router by means of a menu. There are assorted choices you can set to alter.