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Forum Replies

  1. Thanks Rene - so am I right in thinking there is no implicit deny on a route map used as an export map in this process? Anything not matched on the route-map will just use the default settings configured.

    Normally when applying a route-map to a neighbour in IPv4 (e.g. neighbor X route-map Y) if something isn’t positively matched in the route-map, it will get dropped?

  2. Hi Chris,

    It still has the implicit deny but when you use a route-map as an export-map, it only tells the router which route-targets to add. When you use a route-map with a neighbor for a routing protocol, it works as a filter for routes.

    For example, this is the default route-target on PE1:

    ip vrf CUSTOMER
     rd 1:1
     route-target export 1:1:

    And we use this export-map:

    PE1(config)#ip prefix-list CE1_L0 permit
    PE1(config)#route-map EXPORT_MAP permit 10
    PE1(config-route-map)#match ip address prefix-list CE1_L0

    Then we end up with:

    PE1#show ip bgp vpnv
    ... Continue reading in our forum

  3. Hi Rene,

    Thank you for your nice lesson . Need to know more about the “Additive” keyword functionality . Can you please more brief on it?


  4. Hello Zaman

    The additive keyword will allow you to add an export map without overwriting the previously configured ones. For example, if you configure the following:

    PE1(config)#route-map EXPORT_MAP permit 10         
    PE1(config-route-map)#set extcommunity rt 1:1 

    and then at a later time you configure this:

    PE1(config)#route-map EXPORT_MAP permit 10         
    PE1(config-route-map)#set extcommunity rt 3:3 

    The result is that the 1:1 entry will be overwritten by the 3:3 entry. However, if you use the additive keyword like this instead:

    PE1(config)#route-map E
    ... Continue reading in our forum

  5. Hi @lagapides
    So will this additive keyword still cause my routes to stay at the other end PE orwill it be removed from the far end PE node ?

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