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Forum Replies

  1. Hi Rene, i am confused to understanding this concept. please help.

    So what I could figure-out so far is :-

    "In a transit AS scenario, Enabling BGP sync made sense. because otherwise our ASBR router will advertise EBGP routes (learned from EBGP neighbor) to other internal routers as well and ultimately may become a transit AS for both EBGP neighbors which we don’t want.

    So the rule said if we learn a route from IGP then only we should advertise it to other EBGP neighbor. that means we are only advertising network that we own.
    But now this rule is not needed in t

    ... Continue reading in our forum

  2. Hi @chriscowboyfann,

    I didn’t watch the video again but if I was talking about the AD, it’s 110 for OSPF. If the router has to decide if it wants to use routing information from routing protocol X or Y then it will look for the AD. For example, is learned through IBGP and OSPF…t will look at the administrative distance and prefers the lowest value. It will use OSPF since it has an AD of 110, compared to 200 for iBGP.

    The local preference is used when the router has learned multiple paths for a network through BGP, and it has to make a decision which

    ... Continue reading in our forum

  3. Hey Rene, I don’t quite understand how your BGP table can show RIB Failure in sub-section “BGP synchronization disabled” for R4’s route to, you have no IGP providing route to it, how can it be in RIB failure ?

  4. Hi Rene,

    I have a very basic doubt. We configure the sync rule under the BGP configuration, so in this case, how would it know that there is a routing table entry for IGP route. Is the check for routing table entry performed by the router itself or the individual process such as BGP, OSPF or EIGRP.

    Thank you!

  5. Hello Ishan

    When the sync rule is enabled, the route will not be installed in the routing table unless the IGP being used has learned about it.

    It is not looking for the route in the routing table, since it will never be there because this is a condition for installing a route into the routing table. It will only be installed if this condition is met.

    What the sync rule does is cause the router to first check if the route is “known” by an IGP. What this means is it looks in the topology table in the case of EIGRP, or the OSPF Link State Database to see if the

    ... Continue reading in our forum

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