974202 - ipv6 default route needs to be fixed on core1.scl3.mozilla.net

Status: RESOLVED FIXED

(Infrastructure & Operations Graveyard :: NetOps: DC Other, task)

Description

[Dave Curado :dcurado]

border1.scl3 and border2.scl3 connect to core1.scl3 and core2.scl3.
core1 and core2 learn a default IPv6 route via BGP with border1 and border2.

fw1.scl3 connects to both core1 and core2.
There is an ospfv3 adjacency between fw1 and core1 as well as core2.

In order for fw1.scl3 to learn a default IPv6 default route, on core1 and core2
there is a policy to import an IPv6 default route into ospfv3.
This works.
However, there is a unexpected side effect. When fw1 learns a default from
the core1, it advertises that default route to core2.  And, vice versa.
The result is that core1 has an IPv6 default route that points to fw1.
Not what we want.

There are a variety of ways that we could fix this.
My suggestion is to remove the policy on core1 and core2 that injects
ipv6 default into ospfv3, and then to create two IPv6 static defaults
on fw1, one that points to core1 with normal preference, and one that
points to core2 with a lower preference.  

This should end up with the desired result -- fw1 will have an IPv6 default
route, and core1 and core2 will point default to border1 and border2.

Comment 1

[Dave Curado :dcurado]

This work has been completed.
fw1.scl3 now has a static default pointing to core1.scl3 and a floating static default pointing
to core2.scl3.

core1 and core2 had their ospf3 export statements removed, so they now believe the 
ipv6 default they are learning from border1 and border2.