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  • 1.  L3VPN - Do Not Perform Next-Hop Self

    Posted 03-31-2021 18:04
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    I have an MPLS L3VPN built where I am using BGP to a CE device. I would like to advertise the L3VPN VPNv4 routes without changing the next-hop. It looks like there is a parameters available in routing policy action for this purpose: 'then next-hop peer-address'. However, the next-hop is still being changed to the PE router's loopback address. How can I stop this behavior? Basic config is attached.

    Attachment(s)

    txt
    test_l3vpn_config.txt   2 KB 1 version


  • 2.  RE: L3VPN - Do Not Perform Next-Hop Self

    Posted 04-01-2021 19:35
    Are you saying that instead of this: 

    you want this? 



  • 3.  RE: L3VPN - Do Not Perform Next-Hop Self

    Posted 04-01-2021 23:28
    Yes, exactly. I'm not sure whether this is possible. I realize that PE1 in the example has to allocate a label for the route advertised, then that PE2 must be able to resolve the next-hop address in it's inet.3 table. Egress Peer Engineering (referenced below) would allow for resolution of CE1's peer address at the PE2 router, but not sure that works for VPNv4 routes.

    https://www.juniper.net/documentation/en_US/release-independent/solutions/information-products/pathway-pages/epe-fundamentals.pdf


  • 4.  RE: L3VPN - Do Not Perform Next-Hop Self

    Posted 04-01-2021 23:59
    Then the answer is NO! you cannot change the next-hop behavior.  The BGP next-hop of a VPN-IPv4 route has to be the PE's own address. You cannot change that.   RFC 4364:  

    " When a PE router distributes a VPN-IPv4 route via BGP, it uses its own address as the "BGP next hop".
    Also, EPE works with BGP-LU and SR as far as I know.

    Regards,