Is this a typo in Lammle's 100-101?

Page 332, figure 8.1. How is this network even possible? I even tried to replicate it in gns3 and all I got was overlap errors. But then Lammle proceeds to 'show ip route' supposedly from this network?

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Comments

mrrhtuner

I don't have GSN3 at work to test it but I'm not certain why it wouldn't work.

Each interface on the router is on a different subnet. I'll check this out later at home.

theodoxa

It won't work because the subnets overlap. A Cisco router will not allow you to assign an IP Address to an interface if it would overlap a subnet directly connected to another interface on the same router.

aftereffector

What he said ^^^

Just for a sanity check, I labbed it, and no, it doesn't work.

late_collision

Bellman80 wrote: »

Page 332, figure 8.1. How is this network even possible? I even tried to replicate it in gns3 and all I got was overlap errors. But then Lammle proceeds to 'show ip route' supposedly from this network?

I just opened my book and what Lammle is trying to illustrate is the longest match rule, or the rule of specificity.

If Lab_A receives a packet to a 10. network on it's Fa0/0 interface, what will the router do with it? Basically he is trying to show you what to look for in the event of network overlap, not how to design one. This is a valuable concept to understand.

Bellman80

I understand that he was trying to explain a different concept, but I wish he would have come up with a valid network to do so, if possible. That example made me question everything I learned about subnetting.

I guess it's a good thing that I notice these things though. Thanks for confirming my sanity, folks!