Cisco Router Boot Process: Finding and Loading IOS Image

The Next Step in Cisco Router Boot Process

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A cisco router is booting and has just completed the POST process. It is now ready to find and load an IOS image. What function does the router perform next?



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A. B. C. D.


When a Cisco router completes the Power-On Self-Test (POST), the next step is to locate and load the operating system (IOS) image. The IOS image is the software that enables the router to operate and provide network services.

The answer to this question is C. The router loads the first image file in flash memory. When the router is turned on, it checks its non-volatile random access memory (NVRAM) to see if a bootable IOS image is stored there. If there is no image, it then looks for an image in the router's flash memory. Flash memory is a type of non-volatile storage that is used to store the IOS image and other system files.

The router loads the first image file in flash memory by default. This is because the Cisco IOS is stored in flash memory as a binary file. The binary file contains the router's operating system and all the necessary files required for the router to operate.

The router can also be configured to load an IOS image from a TFTP server, as mentioned in option B. However, this requires specific configuration changes and is not the default behavior.

Option A is incorrect because the configuration register is a setting that determines how the router boots up and where it looks for the IOS image. It does not dictate the actual process of loading the IOS image.

Option D is also incorrect because the router does not inspect the configuration file in NVRAM for boot instructions during the boot process. Instead, it looks for the IOS image in flash memory first and then other locations if necessary.

In summary, when a Cisco router completes the POST process, it loads the first IOS image file in flash memory by default, unless it has been configured to boot from a TFTP server.