VRF - Lite

Lets small step to core MPLS network, but it is not so core at all :)

It is  called VRF - Lite that VRF concept without MPLS by Cisco ,

 There are guest and trusted internet access for an enterprise;

VLAN 10 - 10.x.x.x Network is used for trusted > VRF BUE
VLAN 20 - 192.x.x.x Network is used for guest network  > VRF RED

 

R1 :

outer ospf 1 vrf BLUE
 router-id 0.0.1.1
 log-adjacency-changes
 network 10.0.0.0 0.0.255.255 area 0
 default-information originate
!
router ospf 2 vrf RED
 router-id 0.0.1.2
 log-adjacency-changes
 redistribute static metric 10 subnets
 network 192.168.0.0 0.0.255.255 area 0
 default-information originate
!
ip route vrf BLUE 0.0.0.0 0.0.0.0 10.0.0.1
ip route vrf RED 0.0.0.0 0.0.0.0 192.168.0.1

R2 : 

router ospf 1 vrf BLUE
 router-id 0.0.2.1
 log-adjacency-changes
 network 10.0.0.0 0.0.255.255 area 0
!
router ospf 2 vrf RED
 router-id 0.0.2.2
 log-adjacency-changes
 network 192.168.0.0 0.0.255.255 area 0
!

R3: 

router ospf 1 vrf BLUE
 router-id 0.0.3.1
 log-adjacency-changes
 network 10.0.0.0 0.0.255.255 area 0
!
router ospf 2 vrf RED
 router-id 0.0.3.2
 log-adjacency-changes
 network 192.168.0.0 0.0.255.255 area 0
!
end

PS 1 : Also don't forget to configure proper ospf routing R4 and R5 with vrf configs.

With ospf routing we have full connectivity between OSPF domain like MPLS core !

PS : The PC's at access circuit are routers actually :)

PS 2: I share an example for one of them ;

At R3 ; 

router ospf 10 vrf BLUE

network 10.0.0.0 0.0.255.255 area 0

PC3:

router ospf 10

network 10.0.0.0 0.0.255.255 area 0

R3 and PC3 is ospf neighbour now !

Lastly ;

we need to redistribute OSPF 1 into OSPF 10 and vice versa ;

R3:

router ospf 1 vrf BLUE

redistribute ospf 10 vrf BLUE subnets      

router ospf 10 vrf BLUE

redistribure ospf 1 vrf BLUE subnets

Now, P3 is full connectivity with R5 that is default gateway for trusted networks.