Basic ospf config

cdad2000

Hey all,

Just confused, when configuring OSFP the ip address position on an interface, what is the difference between using the exact interface address or the network address?

Let's just say for example wan S0 = 192.168.179.2 /30

would it make a difference using 192.168.179.2 or 192.168.179.0

thanks for your help.

networker050184

The network statement just identifies what interfaces to include into the OSPF process. Come on you should know that having the CCNA , might be time for a little review. In other words no it doesn't make a difference.

bmauro

Also lets say you had a couple interfaces you wanted to include in the OSPF process:

Say:

Eth0 - 172.16.1.1 /24
S0/0 -172.16.2.2 /24
S0/1 -172.16.3.3 /24

If you wanted all three to be included you would just do a network 172.16.0.0 0.0.255.255 area x

But lets say that you wanted only the Eth0 and S0/0 included then you would just do:

172.16.1.1 0.0.0.0 OR 172.16.1.0 0.0.0.255
AND
172.16.2.2 0.0.0.0 OR 172.16.2.0 0.0.0.255 - plus the area

So the difference is that you can control how "generic" you want to be or exactly which interfaces are included.

In my opinion I find it much easier to read and less guess work when I just include the exact match for the interface.

bmauro

And the always helpful cisco link......

http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124cg/hirp_c/ch15/1chospf.htm#wp1000989

cdad2000

Wow, thanks for your help . And thanks for the link. I need a review on steriods.

cisco_trooper

Read Chapter 8 in Routing TCP/IP Volume I, Second Edition. That should cure your problem in relation to OSPF.