This is one of multiple SPF videos.
I was asked to explain Oh SPF multiple areas and this is one of multiple videos helping explain how
SPF works when you have multiple areas configured router 5 is another area border router it exists between
area zero and Area 2.
So bypass the initial configuration dialog
and configure this of four out of five interface gigabit.
Zero zero and no shut IP address 10 1 4 2 slash 24 mosque
so that was the IP address configured on gigabit 0 0 on interface gigabit 0 1 IP address 10 1 5 1 24
mosque and I'll create a loop back of Triple Five
so do show IP interface brief IP addresses are configured on the various interfaces I forgot to no shut
gigabit.
There 1 so there we go on this Friday we are going to configure always P.F..
But what we're going to do now is make sure that we configure and I'll do it slightly differently now.
We'll configure gigabit 00 in area zero so we're saying this interface gigabit 00 which has an IP address
of 10 1 4 2 is going to be put into area zero because of the mosque used here.
It's an inverse mosque.
I'll also put the loop back of the router into areas zero and then I'll configure
gigabit.
Is there a 1 in Area 2 so show run section who is P.F..
That's the configuration of SPF on the.
Show IPO SPF interface brief at the moment.
We only have SPF enabled on one interface.
And that's because I made some mistakes so let's read do that no network for 444
should be network.
5 5 5 5
show IP 0 SPF
interface brief we've got 0 SPF running on the loop back and gigabit 00 so show IP interface brief 10
1 5 1 is configured on gigabit 0 1.
Let's see what I did wrong in 0 SPF I put this as a zero.
Rather than using the right mosque so no network 10 1 5 0.
This should have been done
like this so show IPO SPF interface brief that looks better or SPF is configured on three interfaces.
Show IP round.
We are learning intra area runs into area roots and external rots and root of 5 should be able to ping
router 1 which it can and we can see the output on wrote a 1 OK.
So the lower strata to configure is right 6.
This is an internal router all interfaces on this proto belong to area to sell bypass the initial configuration
dialog and all configured the router should be right a 6 interface gigabit 00 no shut IP address 10
1 5 2
so that's the IP address on gigabit 00 interface loop back 0 IP address quadruple 6
as follows router over SPF 1 network and I'll just do it this way to keep it simple all interfaces.
In this example belong to Area 2 so show IP SPF interface brief show IP SPF interface brief shows us
that 0 SPF is running on both gigabit 00 and the loop back show IPO SPF neighbor shows us our neighbor
relationship to write of 5 show ip route shows us our writing table.
Now here we don't see any intra area runs because this Ethan it interface and the loop back of the local
router are seen as directly connected rather than being advertised by a writing protocol.
So we see in our area ruts and quite a few of them as well as external rods wrote a six should be able
to ping wrote a one which it can and we can see the debugger and write a 1 to show IP or SPF database.
Notice that on Route 6 this command shows us only Area 2 because the rod is only configured in Area
2 it sees that rod a 6 and write a 5 are configured in area to seize that rod of 5 is the designated
Rado on the Ethernet segment in Area 2 it sees a range of LSD these are into area Roth's LSA types 3
it sees a type for LSA which is a summary ISP are LSA and it sees external ruts.
So there you have an example of many LSA types that you get in 0 SPF LSA type 1 Rod LSD LSA type 2 network
link LSD
top 3 summary LSD type 4 EPR LSD and top 5 external LSD.
Let's have a look at Rider 5 which has interfaces in multiple areas so show IPO SPF database you'll
notice it displays information for area 0 as well as for Area 2 so on area 0 we have 3 routers in areas
0.
We have 2 designated routers in area 0 So to net the link states these are summary LSD or rots coming
from other SPF areas.
There is one autonomous system border Radha LSA then we see similar information for Area 2 and right
at the end we see the external LSD or LSA top 5 there was an example of how to configure multi area
o SPF.
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