I know that OSPF will only multicast out hard interfaces if at least one of the interfaces subnets falls within the network subnet.
But once an interface is active, will OSPF also distribute other subnets on the same hard interface that are not with in the network subnet?
If so how do I get OSPF to NOT rebroadcast over and over again for each additional subnet on that interface but only announce that subnet in its primary
multicast?
Thanks, Homer W Smith, CEO Lightlink
Hey. It will send only network based advertisments.
OSPF, by design will learn and advertise all subnets that it learns to every other router in the area.
What problem are you trying to solve by limiting the subnets that are advertised?
The problem is not limiting what subnet is advertised, the problem is OSPF advertising multiple streams of data,
one for each subnet.
Thus if network is 0.0.0.0/0 and router has
10.16.0.1/29
10.16.17.3/24
10.16.17.4/24
ospf will send 3 completely independent streams of data one for each subnet, advertising all subnets.
If however network is set to 10.16.0.0/29, only one stream is sent from 10.16.0.1 → multicast, advertising
all subnets on the interface. Check out how many independent streams are multicast our of each interface if your network is 0.0.0.0/0
and the interface has more than one subnet on it.
Homer
Homer