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MPLS Hub and Spoke

Hello,

  Is there any configuration document which explains about MPLS hub and spoke without any tunnel? The requirement is to avoid spoke to spoke communication directly and all traffic from spoke 1 to spoke 2 should be through the hub site, even though the spokes are connected to the same PE router.  I tried lab it with VRF and route import/export, but the P router knows all the route and when it reaches the P router, it has the more specific route to spoke 2 and routes it.  I wanted to avoid using a GRE/MGRE tunnel between PE to PE and carrying vrf in PE router (spoke 1, spoke 2) end to end.

Is there an option available to achieve this scenario?

Thanks in Advance

Karthik

  • WAN Routing and Switching
5 REPLIES

MPLS Hub and Spoke

New Member

MPLS Hub and Spoke

Hi Karthik,

what is the ultimate goal here?

are you managing the CEs or the PEs. It's not that much complicated if you are managing any.

If you r managing the MPLS cloud then P routers should not have the customer's routes in it is routing table and then you may use route target export/import to acheive the requiremnets.

If you are managing the CEs think of adding a community value on the hub routes and accept only this value at the spokes.

Ahmed

MPLS Hub and Spoke

Hello Ahmed,

  Thanks for the update. If we are managing the P/PE router. The PE router will have the route target export and import in spoke and hub side, but the P will have all the specific routes from hub and all the spokes. Should we have route target configured at the P router(vrf)

Thanks

Karthik

Hall of Fame Super Blue

Re: MPLS Hub and Spoke

Karthik

As Ahmed says the P routers should not have the customer routes.

In an MPLS network the P routers only know how to get to other P routers and the PE routers but they have no knowledge of the networks outside of the MPLS network ie. the customer routes.

The PE routers know the routes that the P routers know so they can send traffic to each other and they also know the routes for the customer networks that are advertised from CE devices.

So when a customer packet comes in to the ingress PE router first lookups where to send the traffic to get to the destination network. The result of this lookup will be another PE. Then it has to find out how to get to the egress PE ie.which P router to send the traffic to.  The P routers on the other hand do not care about the customer network, they simply label switch from one P router to another unitl it gets to the egress PE.

So if your P routers are seeing the customer routes it sounds like there is something wrong in the configuration.

Jon

MPLS Hub and Spoke

Hello Milan,

  Thanks. I will go through the links provided and update with the status.

Regards

Karthik

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