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  • 1.  local-preference under protocols bgp group not modifying received-prefixes

    Posted 01-19-2012 16:44

    Hi!

     

    I currently have to almost identical bgp groups but for various reasons I would like to have a higher localpref on routes received from one group than the other.

    I want to use the same import policy on the groups so for that reason I would like to set the local-preference outside of this. When i set localpref via policy-statement, I can see from show route x.x.x.x/y all that it's set according to the rule in the policy-statement. However, when I remove the term setting the local-preference from the policy-statement and include it on the group-level instead, it's not set, show route x.x.x.x/y all shows it's just set to default. When set on group-level, show bgp neighbor shows the correct Localpref. Am I missing something here? This is on a mx80 running 10.4R3.4.


    #mx80bgplocal-preference


  • 2.  RE: local-preference under protocols bgp group not modifying received-prefixes

    Posted 01-20-2012 03:18

    Dear

     

    Just to make sure you have to apply it in the group level at the sender (the router export the network x.x.x.x/y). Please confirm

     

    Thanks,

    Mohamed Elhariry

    JNCIE-M/T#1059, CCNP & CCIP



  • 3.  RE: local-preference under protocols bgp group not modifying received-prefixes

    Posted 01-24-2012 06:24

    Hi Mohamed,

     

    This is the relevant configuration:

    gustav@sto1-ro01> show configuration protocols bgp group xxx-route-servers 
    type external;
    description "xxx Route Servers";
    local-preference 110;
    local-address y.y.y.y;
    export bgp-peer-export-xxx-rs;
    neighbor y.y.y.x {
        description "xxx RS#1";
        peer-as xyz;
    }
    neighbor y.y.y.z {
        description "xxx RS#2";
        peer-as xyz;
    }

     Thanks!



  • 4.  RE: local-preference under protocols bgp group not modifying received-prefixes
    Best Answer

    Posted 01-24-2012 13:21

    Hi,

     

    Kindly check this link

     

    http://www.juniper.net/techpubs/software/junos/junos94/swconfig-routing/configuring-the-bgp-local-preference.html

     

    The LOCAL_PREF path attribute is always advertised to internal BGP peers and to neighboring confederations. It is never advertised to external BGP peers.

     

    When using policy and apply it as import policy, it will work as you do action modification and modified the LP attribute from 100 to another value and re-advertise it to your internal neighbor.

     

    Thanks,

    Mohamed Elhariry

    JNCIE-M/T#1059, CCNP & CCIP



  • 5.  RE: local-preference under protocols bgp group not modifying received-prefixes

    Posted 01-25-2012 01:58

    Thanks Mohamed, that explains it.

     

    I expected local pref to be changed for imports but see now that it's only applied to exports when used in this way.