@Cecil-Burrowes,
Sorry it took a little longer to answer this question, I've been really busy with show creation but I had a few minutes this morning to answer.
In Don's lab scenario, He configures the 2 clients as a individual customer's connecting to his ISP router for OSPF1 area 0. Each client here is located of a single interface interface s1/0.1 , interface s1/0.2
Router(config)# router ospf 1 vrf customer1
Router(config-router)# network 10.1.1.0 0.0.0.3 area 0
Router(config-router)# default-information originate always
Router(config)# router ospf 2 vrf customer2
Router(config-router)# network 10.1.1.4 0.0.0.3 area 0
Router(config-router)# default-information originate always
So that both of these were part of the original configuration of the router.
When we add a new branch on loopback9, this is not part of the original network to ospf1 vrf customer1. Note above there is no network statement for 192.168.1.1/24.
So two possibilities here exist. He could enter an ADDITIONAL network statement:
Router(config)# router ospf 1 vrf customer1
Router(config-router)# network 192.168.1.0 0.0.0.255 area 0
Don's way of doing it works very well too and fast which is to add the Router(config-if)# ip ospf 1 area 0 while configuring for the new branch office of customer1.
So it comes down to it's a matter of choice but Don's is quicker and doesn't require him to do any wildcard masks. It simply says hey, regardless of the network on this interface add it to ospf1 area 0 This is great if customer decides later to renumber the ip address to match the original IP address scheme.
I hope this helps!
Cordially,
Ronnie Wong
Edutainer Manager, ACI Learning [ITPRO]
*if the post has answered the question, mark as solved.
**All "answers" and responses are offered "as is" and my opinion. There is no implied service, support, or guarantee by ITProTV.
