OSPF Woes , Kindly clarify my configuration :

satishtech

ROUTER0
interface GigabitEthernet0/0
ip address 193.25.25.65 255.255.255.192
duplex auto
speed auto
!
interface GigabitEthernet0/1
ip address 173.16.1.1 255.255.255.0
duplex auto
speed auto

router ospf 10
log-adjacency-changes
network 193.25.25.0 0.0.0.63 area 0
network 173.16.1.0 0.0.0.255 area 0

ROUTER1
interface GigabitEthernet0/0
ip address 173.16.1.2 255.255.255.0
duplex auto
speed auto
!
interface GigabitEthernet0/1
ip address 192.168.1.1 255.255.255.0
duplex auto
speed auto

router ospf 10
log-adjacency-changes
network 192.168.1.0 0.0.0.255 area 0
network 173.16.1.0 0.0.0.255 area 0

satishtech

I thought I had figured it out.
It turns put I must add this line to Ping across networks.

To be added on Router0
network 193.25.25.0 0.0.0.255 area 0

This line network 193.25.25.0 0.0.0.63 area 0
is not enough ?

OfWolfAndMan

0.0.0.63, or 255.255.255.192 supports only 64 hosts per subnet. In essence, you were only initially advertising 193.25.25.0-193.25.25.63. You could've done the statement network 193.25.25.64 255.255.255.192 and you would've been good as well

satishtech

Thank You wolf man.
would it be ok if I use the wild card mask 0.0.0.127 ?

OfWolfAndMan

Yes that works as well.

Heero

satishtech wrote: »

Thank You wolf man.
would it be ok if I use the wild card mask 0.0.0.127 ?

I would not typically suggest that you use a network statement that covers unassigned address ranges. The network statement basically says "if the IP address of local router's interface is within the range of the network statement, advertise that interface and subnet into ospf."

If you want to match an interface on your router with the IP 193.25.25.65/26, best practice is to match the entire subnet (and only the subnet) or to match on the single IP configured on the interface.

So either:

network 193.25.25.64 0.0.0.63 area 0

or

network 193.25.25.65 0.0.0.0 area 0

Keep in mind I'm just saying that this is best practice. And if you actually have the 193.25.25.0/26 network on an interface on the router, I wouldn't have any issues with using the "network 193.25.25.0 0.0.0.127 area 0" to match both interfaces.

EdTheLad

Heero wrote: »

Best practice is to match the entire subnet (and only the subnet) or to match on the single IP configured on the interface.

So either:

network 193.25.25.64 0.0.0.63 area 0
or
network 193.25.25.65 0.0.0.0 area 0

Best practices would be to match the the single interface address with a 0.0.0.0 mask. If you have multiple interfaces rather than having loads of network statements you could use a larger mask to incorporate them all into one statement. In the real world best practices is to enable ospf under the interface, and forget about the network statement altogether.