VXLAN Flood and Learn Multicast Data Plane

Lessons Discussion
1

This topic is to discuss the following lesson:

2

Hello Everyone,

What will happen if we will not enable pim on loopback interfaces specially on spine ?

Regards

3

Hello Amit

Strictly speaking, you don’t need to enable PIM sparse mode on the loopbacks of the devices you are using. However, in the specific topology, Rene has chosen to use the loopback interface of the spine switch as the address of the RP. This is typically best practice as you can see from this lesson here. So for this particular case, if you don’t enable PIM sparse mode on the loopback, it cannot participate as the RP of the topology.

I hope this has been helpful!

Laz

4

Hi,

Why we need to specify “ip ospf network point-to-point”?

Thanks

5

Technically it would work without.

By default, OSPF uses the broadcast network type on Ethernet interfaces. This means it will do a DR/BDR election.

This isn’t needed because we only have p2p links in between spine and leaf switches. The LSDB will also be smaller.

For a lab in doesn’t matter but for a large spine and leaf topology, it does. Here is some more info: