In this video, I'm going to demonstrate how OSPF Version three routers can form neighbor relationships
without you manually configuring IP addresses on interfaces.
In other words, in this topology, we'll form a neighbor relationship between router one and router
two without configuring IP version six addresses on the gigabit zero zero interfaces.
This will demonstrate how OSPF forms neighbor relationships using link local addresses and doesn't require
IP version six addresses to be configured or IP version four addresses.
So in this topology, the two routers have just booted up.
There is no configuration on the routers.
I'll bypass the initial configuration dialog so that we can configure the routers manually.
So the router on the left will call right of one show IP route.
Shows us that they are no IP version for routes available on this router show IPV six route shows us
that they are no IP version six routes available on this router at the moment.
These routers have just booted up again with no configuration, so show IP route no IP version for routes.
Show IPV six route no IP version six routes.
Show IP interface brief no IP addresses configured on router one show.
IPV six interface.
Brief shows us that there are no IP version six addresses.
Same on the site show IP interface brief no IP version for addresses show IPV six interface brief note
IP Version six addresses configured.
Okay.
So IPV six unicast routing needs to be enabled for us to use OSPF.
What we'll do now is enable OSPF as a routing protocol.
The router will complain, as you can see there, that no router ID can be selected and that's because
we have no IP version for addresses configured.
So I need to select a router ID in dotted decimal notation such as the following.
IPV six unicast routing.
IPV six.
Router OSPF one.
Once again, we need to configure a router id.
I'll configure the side as 2.2.
.2.2.
So show.
IPV six OSPF Interface brief shows us that OSPF is not enabled on any interfaces on the rider.
What we have to do is go on to interfaces.
And enable IPV six on an interface.
And then enable OSPF on that interface.
So on this side, gigabit is zero zero.
IPV six enable to enable IPV six on the gigabit zero zero interface and then IPV six OSPF process ID
is one area will set to zero.
So now show IPV six OSPF Interface brief shows us that OSPF is enabled on gigabit zero zero with a process
ID of one in area zero.
At the moment the state is down and that's probably because I didn't enable the interface.
So let's do that.
So now show IP.
V6 OSPF interface brief.
Notice the state is set to wait on no shut the interface on this side.
Show IP V6 interface OSPF interface brief OSPF is enabled on gigabit zero zero in area zero using OSPF
process one.
The state is wait at the moment show IPV six ospf neighbor.
We are forming a neighbor relationship with a brother with neighbor ID 1.11.1 on this side show IPV
six OSPF neighbor.
Notice the neighbor relationship has now moved to start and.
Has just moved to full.
So you can see the neighbor relationship went to full there.
Writer one is a BTR.
And on this side we can see that rather two is the designated rider.
So we have formed a neighbor relationship.
With the other rota without enabling an IP version six address on the gigabit zero zero interface.
So notice there's no IP version for address and there's no IPv6 address enabled on this interface.
And the same is true on the side, but.
We do have a OSPF neighbor relationship with the other router and if we look at the routing table.
We can see at the moment that we have a local network in the routing table but no other route exist.
The show, IPV six rather shows us that a local address is configured on gigabit is zero zero.
So show IPV six interface gigabit.
Zero zero.
Shows us that the interfaces up IPV six is enabled.
This is the link local address on the interface.
This router has joined various multicast groups, including two OSPF groups.
This is all devices on the local segment.
On the side show run interface gigabit is zero zero.
Or show IPV six interface gigabit zero zero rather shows us the link local address on this side.
So to prove that writing works.
On Rata one.
I'll configure a loopback.
IP address.
So IPV six address and in this case we'll call it 2001 Facebook.
One colon.
Colon 1/1 28.
On this site.
Interface loopback.
Zero.
IPV six Address 2001 Facebook.
Colon.
Colon two 128.
Notice those are 128 networks.
So these two are separate networks.
Show IPv6 route.
We have a loopback address in the routing table, but we don't see this address.
Because we need to advertise that network into OSPF.
So now once that network gets advertised, we should see it available in the routing table of router
two.
And there you go.
We have learnt about Facebook one.
Via the link local address of writer one.
Once again, show IPV six interface gigabit.
Zero zero.
This is the link local address of Writer one, and that's the address that we are learning the route
from.
On the side show IPV six route.
We haven't learnt.
About the loopback on this side, and I think I made a mistake.
So let me double check the configuration I made to this zero rather than a two.
So what I'll do is remove that IP address.
And put it back.
As to colon.
Colon two.
IPV six.
SPF one, area zero.
Once that network gets advertised, we should see it on rather one.
And there you go.
The brunch is now available on Rata one.
So we've learnt the address via OSPF.
Let's try and ping the address.
What do you think?
Will it work?
So ping.
IPV six.
This address.
Does it work?
Yes, it does.
We can ping the loopback of router two on this side.
Show IPv6 route.
Can we ping?
The loopback.
Yes, we can.
Notice you don't have to specify IPv6.
The router is intelligent enough to work out that this is an IPV six ping debug IPV six icmp.
Let's do that ping again.
Notice we see that an echo request was received and a reply was sent.
So again, the gigabit is zero zero interfaces of both these riders.
Don't have either an IP version for address or an IP version six address configured.
As soon as we enabled IP version six on the interface, a link local address was allocated as shown
here and OSPF users link local addresses for neighbor establishment and route advertisement.
And that's what I've demonstrated here.
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I wish you all the very best.