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Table of Contents

Administration Guide

Next hop recursive resolution using other BGP routes

By default, BGP routes are not considered when a BGP next hop requires recursive resolution. They are considered when recursive-next-hop is enabled. Recursive resolution will resolve to one level.

To consider BGP routes for recursive resolution of next hops:
config router bgp
    set recursive-next-hop enable
end

Example

To see the change in the routing table when the option is enabled:
  1. Check the BGP routing table:

    # get router info routing-table bgp
    Routing table for VRF=0
    B       10.100.1.4/30 [200/0] via 10.100.1.14 (recursive is directly connected, R560), 00:02:06
  2. Enable BGP routes for recursive resolution of next hops:

    config router bgp
        set recursive-next-hop enable
    end
  3. Check the BGP routing table again:

    # get router info routing-table bgp
    Routing table for VRF=0
    B       10.100.1.4/30 [200/0] via 10.100.1.14 (recursive is directly connected, R560), 00:02:15
    B       172.16.203.0/24 [200/0] via 10.100.1.6 (recursive via 10.100.1.14, R560), 00:00:06

    The second BGP route's next hop is now recursively resolved by another BGP route.

Next hop recursive resolution using other BGP routes

By default, BGP routes are not considered when a BGP next hop requires recursive resolution. They are considered when recursive-next-hop is enabled. Recursive resolution will resolve to one level.

To consider BGP routes for recursive resolution of next hops:
config router bgp
    set recursive-next-hop enable
end

Example

To see the change in the routing table when the option is enabled:
  1. Check the BGP routing table:

    # get router info routing-table bgp
    Routing table for VRF=0
    B       10.100.1.4/30 [200/0] via 10.100.1.14 (recursive is directly connected, R560), 00:02:06
  2. Enable BGP routes for recursive resolution of next hops:

    config router bgp
        set recursive-next-hop enable
    end
  3. Check the BGP routing table again:

    # get router info routing-table bgp
    Routing table for VRF=0
    B       10.100.1.4/30 [200/0] via 10.100.1.14 (recursive is directly connected, R560), 00:02:15
    B       172.16.203.0/24 [200/0] via 10.100.1.6 (recursive via 10.100.1.14, R560), 00:00:06

    The second BGP route's next hop is now recursively resolved by another BGP route.