VRF

[Johnson_Mo]

Hi Team,

I have couple VRFs setup on R5 with static route from each VRF on R5 pointing back to R4:

ip route vrf_Name 1.1.1.0 255.255.255.0 1.1.1.2.

since R4 interface is on global table, how would static route from R4 to VRFs works. same as normal? ip route network destination/mask + next hop? BTW, interface on R4 can ping interface on R5 even though R5 int is in VRF. 

[MHM Cisco World]

Ok let talk little about vrf 

Are there any vrf field in IP header ?

The answer NO 

So one side use global and other use vrf can connect to each other 

The issue start when we need to use static or igp' here we need route leaking between VRF.

MHM

[Johnson_Mo]

if I do any static route from global router or interface

ip route (ip of VRF on R5) + next hop: ip router + vrf ip/24 1.1.1.2 

it wont work then? 

[MHM Cisco World]

Here there is direct connect 

One side use vrf other use global 

Static route 

You can use in vrf side for lan behind global router side 

Ip route vrf x.x.x.x x.x.x.x next-hop  

And you can use in global side for lan behind vrf router side 

Ip route x.x.x.x x.x.x.x next-hop

We need route leaking when both vrf and global in same router' other there is multi vrf in rourer 

Again vrf not pass throught ip header

MHM

[Johnson_Mo]

my initial post says that one router is on global and the other is on vrf, so I need static routes from lans behinds R4 to VRFs behinds R5.  got my answer and thanks for the replies. 

[MHM Cisco World]

You are so welcome 

Have  a nice day

MHM

[M02@rt37 · Accepted solution]

Hello @Johnson_Mo 

Yes, the static route configuration on R4 to reach the networks in VRFs on R5 would be similar to normal static routes. You would configure static routes on R4 using the syntax:

ip route vrf VRF_Name network_destination network_mask next_hop

So, for example, if you have a VRF named "VRF_Name" on R5 and you want R4 to reach the network 1.1.1.0/24 in that VRF, you would configure something like:

ip route vrf VRF_Name 1.1.1.0 255.255.255.0 <next_hop_IP_for_R5>

Make sure the next hop IP address is reachable from R4 and is within the context of the global routing table.

As for the ping working between R4 and R5 interfaces even though the interface on R5 is in a VRF, this is expected behavior. The VRF separation is for the traffic passing through the router, not for the router's own interfaces. The router itself operates in the global routing table context, so the interfaces can communicate directly without considering the VRF configuration.

[Johnson_Mo]

thanks for the details boss! on the same topology, I have Mcast source from R4 to R5. I have a VRF on 5 that needs to join to two RPs sourcing from R4 . As you know, VRF can join to one RP at a time. is there a way to make  a VRF joining multiple RPs? 

[MHM Cisco World · Accepted solution]

After edit original post it clear.

Hope my answer cover it.

MHM