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  1. Hi René,
    good lesson i read in detail
    I am not a BGP expert as i am studying now (only) for CCNP
    I read other sources for description of attributes (i dont know if i may give this source name)
    This (well known) source give 2 more attributes

    • the first one between 8 (Shortest IGP path to BGP next hop) and 9 (Oldest Path) he call “Multipath”: determines wether or not multiple paths need to be injected into the routing table, and continues if the best path is not yet selected.
    • the second between 10 (router-id) and 11(neighbor IP address) he call “Minimum Cluster L
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  2. Hi Dominique,

    The link @lagapides added is the most complete list of BGP attributes and the path selection:

    https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13753-25.html

    I didn’t include multipath because by default, it’s not enabled in BGP. Internal and external BGP only install a single best path (unless you enable multipath). If you do use multipath, it’s good to know how BGP deals with it.

    The minimum cluster list length is a similar example. It only applies when you use BGP route reflectors. There are also some exceptions when yo

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  3. Hello Carlo

    When configuring attributes such as weight (or any attributes in BGP), you must keep in mind that they affect the choice of route based on the same routing protocol. A router will consider iBGP and eBGP as two separate routing protocols. For example, if you have two routes to 8.8.8.8 via iBGP, then the weight can be used to force the router to route via one path and not the other. If you have one route via iBGP and the other via eBGP, the weight will not affect the choice. It’s like trying to make the router choose a path via iBGP and not via EI

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