Just as in IPv4 is implementation of OSPF with OSPF V3 for IPv6.
If we want to, we can set up an interface as passive.
Now, why would we ever do that?
Let's take a look at that.
It's very same reason we do it for IPv4.
If on this interface right here on R7,
which is 2001, DBA6787, colon colon 7,
if we wanted that interface not to participate in OSPF,
one option would be just to tell that interface
that it's not involved with OSPF,
and it's not participating as part of our OSPF V3 process for Area 1. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
and it's not participating as part of our OSPF V3 process for Area 1.
However, if we did that, that subnet 7 for IPv6,
that subnet 7, if it's not enabled there for OSPF,
it wouldn't be advertised and reachable from the rest of the OSPF domain.
So, one of the benefits of using passive is that we can still include this 7
subnet
for IPv6, the 2001 DBA6787,
but at the same time, we're not receiving hello messages on that interface.
And that's going to prevent us from becoming an adjacent neighbor with some
other device
or some PC or some hacker that's trying to convince our router WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
or some PC or some hacker that's trying to convince our router
that we should become an OSPF neighbor with them.
So, no hello's if the interface is passive.
So, we can include the interface,
but just specify in router configuration mode here on R7
that that interface is passive.
And that way, we have the benefit of advertising the route
without the possibility of becoming neighbor.
Now, to demonstrate that we can't form a neighbor ship
if we make it passive, here's what I propose we do.
Instead of doing it on this one, in the previous set of videos,
we actually worked with passive interface here,
let's go ahead and take an active interface like this one over here. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
let's go ahead and take an active interface like this one over here.
R8's fast-eatenant 4/1,
and it's currently included in OSPF for IPv6.
And if we specify the interface is passive,
it's going to break the adjacency here between R8 and R6,
because it's no longer going to be processing hello messages.
And as a result, we'll break the neighbors ship.
Let's demonstrate that right here between R8 and R6.
And once we've done it, and we validate that, yep,
that the neighbor ship is no longer working,
we'll then go ahead and restore the network to its full functionality
by making this interface F/4-1 not a passive interface. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
by making this interface F/4-1 not a passive interface.
And here we go.
So a moment ago, on R8, we verified we have routes,
we have connectivity.
And if we do a show, OSPF V3, IPv6 neighbor,
we can verify that we are currently in a full adjacency
with R6 based on that router ID.
Again, R6 is this router right here, just north of R8.
So let's do a show run section router, press enter,
just to take a look at our current configuration for OSPF V3.
So here's our configuration,
and we have an address family for IPv6 unit cast. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
and we have an address family for IPv6 unit cast.
And what we're going to do is go into that address family.
And from within that address family,
we'll still be say passive interface,
and then specify the interface that we want to be passive.
And based on our topology,
we're going to specify F/4-1 as a passive interface.
So we'll go into configuration mode,
and then we'll go into router OSPF V3 for process ID1
by typing that in.
And then we'll go into the address family for IPv6 unit cast
by typing that in next.
Then here we'll type in passive dash interface,
and then we'll specify the interface that we want to be passive.
So in our case, it's going to be fast Ethernet 4/1. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So in our case, it's going to be fast Ethernet 4/1.
And before I press enter, let me just verify that's the interface,
sure enough that's the interface on our R8 that's going up to our 6.
So once we press enter here,
that's going to break the adjacency.
And we do a show run section router,
so they look at the config that did that.
So there's our passive interface command
under the address family for IPv6.
And if we do a show IPv6 protocols,
and press enter, here showing us that we still have
fast Ethernet 4/1 associated with area 2,
but because that interface is passive, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
but because that interface is passive,
we're not able to form a naborship with any other router off of that interface.
So let's go back into configuration mode for router OSPF V3 process ID1.
And let's go ahead and take that off with a few up arrow keys.
Then we'll do a control A together beginning of that.
We'll say no passive interface, FAA 4/1,
which should allow us to start processing the lows.
And we've now formed an adjacency with R6.
And that's how we can include an interface
and its associated directly connected network
as part of OSPF, but at the same time, WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
as part of OSPF, but at the same time,
prevent the forming of a naborship
with some other routing device on that same subnet.
Now another cool feature, which is also common to both IPv4 and IPv6 with those
PF, is to make an area not a normal area, but make it a stub or a totally stub
by area.
And that's exactly what we're going to do with the address family for IPv6 in
the next video.
So I'll see you there in just a moment.