CCNP Question

[AndyTemp]

an engineer preformed a router upgrade and after unexpected reboot the router loaded the old IOS version instead of the new one, what is the problem?

1- The configuration register is set to 0x2103

2- The old ios image is corrupted

3- The new ios image is corrupted

4- The boot loader is not present

Thnx in advance

[luis_cordova]

Hi @AndyTemp ,

I would choose the answer 1.
The config register 0x2102 invokes the first image in the flash.
The config register 0x2103 invokes the second image in the flash.

Regards

https://quizlet.com/106137078/configuration-register-settings-flash-cards/

[Joseph W. Doherty]

I would choose #3.

[Georg Pauwen]

Hello,

in addition to the other posts, I was looking at the question, and I think neither answer is correct, technically, but since you have to choose one, it is probably 1. The reason why I think that no answer is actually the right one is that the configuration settings listed below imply the after the upgrade, there should be only two images, not three. So if the config register is set to 0x2103, it loads the third image, which is not there.

0x2101 load default ios from rom (first image in flash)
0x2102 load second image in flash (from tftp if flash fails)
0x2103 load third image in flash  (from tftp if flash fails)

The reason why I don't think it is 3 is that "an engineer performed a router upgrade and after unexpected reboot", which implies that the router was running fine with the new image for a while...

[Joseph W. Doherty]

""an engineer performed a router upgrade and after unexpected reboot", which implies that the router was running fine with the new image for a while..."

I thought the same, further assuming that the router was configured to correctly boot into the new image. Looking at the reference provided by Luis, the 2103 should boot the into the second image, which assuming the old image is present, it would normally be the new image. However, if whatever caused the unexpected reboot also corrupted the new image, I recall boot loaders will generally boot into the first valid image if the primary selected image is "bad", i.e. corrupted.