Solved: ospf config

anitachoi3 · ‎11-20-2008

Hi,

below is my ospf setting,

router ospf 100

network 192.168.1.0 0.0.0.255 area 0

network 172.16.1.5 0.0.0.3 area 1

what is different if I change to

"network 172.16.1.4 0.0.0.3 area 1"

which one is better?

network 172.16.1.5 0.0.0.3 area 1

or

network 172.16.1.4 0.0.0.3 area 1

rdgs

Jon Marshall · ‎11-20-2008

Anita

Generally it would be either

network 172.16.1.5 0.0.0.0 area 1

OR

network 172.16.1.4 0.0.0.3 area 1

The mask just allows you to be very specific about which interfaces to run OSPF on.

As to which is better, well in this case it doesn't make a lot of difference because 172.16.1.4 0.0.0.3 only covers 172.16.1.4 -> 172.16.1.7.

Jon

View solution in original post

Richard Burts · ‎11-21-2008

Anita

It should be the same result.

I believe that you can type it in as:

network 172.16.1.5 0.0.0.3 area 1

but when you do show run I believe that you will find that IOS has translated and it will show up as:

network 172.16.1.4 0.0.0.3 area 1

This is because the address you want to input and the mask are inconsistent. The mask of 0.0.0.3 indicates a subnet address with mask of 255.255.255.252 and IOS will translate what you input to show the subnet address if you use the "subnet" nask.

HTH

Rick

HTH

Rick

View solution in original post

Jon Marshall · ‎11-20-2008

Anita

Generally it would be either

network 172.16.1.5 0.0.0.0 area 1

OR

network 172.16.1.4 0.0.0.3 area 1

The mask just allows you to be very specific about which interfaces to run OSPF on.

As to which is better, well in this case it doesn't make a lot of difference because 172.16.1.4 0.0.0.3 only covers 172.16.1.4 -> 172.16.1.7.

Jon

anitachoi3 · ‎11-21-2008

Hi,

can I config as

network 172.16.1.5 0.0.0.3 area 1

Is it the same result?

rdgs

Richard Burts · ‎11-21-2008

Anita

It should be the same result.

I believe that you can type it in as:

network 172.16.1.5 0.0.0.3 area 1

but when you do show run I believe that you will find that IOS has translated and it will show up as:

network 172.16.1.4 0.0.0.3 area 1

This is because the address you want to input and the mask are inconsistent. The mask of 0.0.0.3 indicates a subnet address with mask of 255.255.255.252 and IOS will translate what you input to show the subnet address if you use the "subnet" nask.

HTH

Rick

HTH

Rick