Working from the my last couple of OSPF posts I am going to try and crystallize some of the material found by working through questions found in Stewart, B,D., Gough, C (2008). CCNP BSCI Official Exam Certification Guide, Fourth Edition. Indianapolis: Cisco Press book.
4. The address 192.100.56.10/21 has been allocated to an interface on the router. This interface alone is to be included in the OSPF process. State the command that would start the process on this interface.
To include this interface alone into the OSPF process
Router_2(config-network)#network 192.168.56.10 0.0.0.0 area number
According to the book (I don’t understand)
Router_2(config-network)#network 192.168.56.8 0.0.0.7 area number
I would have done it like below if I was going to include the entire range, because you are using the /21 which has 2048 nodes/hosts per network ( I hate it when I start doubting myself?!?!)
Router_2(config-network)#network 192.168.56.0 0.0.7.255 area number
Which coincidentally is also in the book (I’m totally confused but moving swiftly along).
The last method is allowing the /24 mask??? why I don’t know (in the book).
Router_2(config-network)#network 192.168.56.0 0.0.0.255 area number
I suppose all of the answers including the first one allows the address which was the goal. Not that allowing the /24 mask or the weird small portion of hosts make sense to me. (why? and where the logic comes from is making me scratch my head).
Resources:
Notes and Notices: This is a part of my personal BSCI notes and research to assist myself in learning and understanding the concepts and theory for the BSCI exam. I learn by making notes reading and writing things down and wish to file them where I cannot lose them. These notes are not to be seen, judged or mistaken for replacements to Cisco recognized and authorized training which I personally support and attend and suggest you undertake if you are going for the BSCI Certification.
Don’t you think the following is also an option:
Enabling OSPFv2 on an Interface
Perform this task to enable OSPFv2 on an interface.
SUMMARY STEPS
1. enable
2. configure terminal
3. interface type number
4. ip ospf process-id area area-id [secondaries none]
5. end
6. show ip ospf interface [interface-type interface-number]
http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/ospfarea.html#wp1053828
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http://blog.ioshints.info/2009/01/when-was-ip-ospf-area-command.html
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Hi Anon,
The above would be a possible solution to the question, although not one of the covered “answers” in the book it is simply enabling ospf on the interface instead of globally which is what the book covers.
This would satisfy the criteria that this interface alone must be added to the OSPF process on the router which will automatically include the IP address that the interface has configured.
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