Quick OSPF Question...

mattipler

Would the answer to the following question...

configure ospf so only the following 172.16.0.0 subnets (see below) will be routed. In other words, if another 172.16.0.0 interface were enabled, such as 172.16.3.0/24, those subnets would not be propagated with OSPF. The only subnets to be routed are :

- 172.16.1.0 /24
- 172.16.10.0 /24
- 172.16.20.0 /24
- 172.16.100.0 /30

Would ospf routing "network" commands required be:

- 172.16.1.0 /24 = network 172.16.0.0 0.0.254.255 area 0
- 172.16.10.0 /24 = network 172.16.0.0 0.0.245.255 area 0
- 172.16.20.0 /24 = network 172.16.0.0 0.0.235.255 area 0
- 172.16.100.0 /30 = network 172.16.0.0 0.0.155.252 area 0

I've got a 99.9999999999% feeling I'm wrong... I'm specifying ranges above rather than a specific subnet. But I'm not sure how to specify one specific subnet.

Any help appreciated.

Cheers guys.

Matt

mattipler

I'm a complete retard ... just realised it should be:

- 172.16.1.0 /24 = network 172.16.1.0 0.0.0.255 area 0
- 172.16.10.0 /24 = network 172.16.10.0 0.0.0.255 area 0
- 172.16.20.0 /24 = network 172.16.20.0 0.0.0.255 area 0
- 172.16.100.0 /30 = network 172.16.100.0 0.0.0.252 area 0

I should be tarred, feathered and pelted with rotten veg.

Ta

Matt

hectorjhrdz

-172.16.100.0/30 = network 172.16.100.0 0.0.0.3 <

---

look!!!


wildmask concepts



luck!!

Pash

easy way to remember it is to minus 255 from the subnet mask:

so a /30 prefix would be 255.255.255.252

so wildcard mask would be 0.0.0.3

fairly easy way to remember it.