cancel
Showing results for 
Search instead for 
Did you mean: 
cancel

Who Me Too'd this topic

OSPF Sham-Link : Redistribution

Chetan Kumar Ress
Enthusiast
Enthusiast
Hi

I was going through sham-link RFC & i found some thing intresting & but confusing.

I had simulated the LAB for sham link & checked that we won't require redistribution between MPBGP & OSPF when we are using sham-link just we need to configure ospf with vrf & shamlink . Becasue sham-link treat itself as a point to point link with unnumbered interface.



4.2.7.4.  Routing and Forwarding on Sham Links

   If a PE determines that the next hop interface for a particular route
   is a sham link, then the PE SHOULD NOT redistribute that route into
   BGP as a VPN-IPv4 route.

   Any other route advertised in an LSA that is transmitted over a sham
   link MUST also be redistributed (by the PE flooding the LSA over the
   sham link) into BGP.  This means that if the preferred (OSPF) route
   for a given address prefix has the sham link as its next hop
   interface, then there will also be a "corresponding BGP route", for
   that same address prefix, installed in the VRF.

My Question :

Can some one clear me that i configured sham-link then do we require redistibution on OSPF to MPBGP for route propogation ?

And

If redistrubution is not requried then what is the meaning of below statement.

   Any other route advertised in an LSA that is transmitted over a sham
   link MUST also be redistributed (by the PE flooding the LSA over the
   sham link) into BGP
Who Me Too'd this topic