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Forum Replies

  1. Rene,

    Great lesson, however I have a question about for the host don’t we need ip pim sparse-mode? I can see on the router we have ip pim sparse-mode.

    Please clarify.




  2. great post.

    with respect to below 2 statements: what is the diff between multicast-routing and PIM command ? both seems to be doing same thing - process the IGMP traffic.

    1.First we enabled multicast routing globally, this is required for the router to process IGMP traffic.
    2.We enabled PIM on the interface. PIM is used for multicast routing between routers and is also required for the router to process IGMP traffic.

    a. from where .40 address came ? does router generates it randomly ?
    b. group address who decides and gives this IP in real time environment ?

  3. Hi,

    R1#show ip igmp groups
    IGMP Connected Group Membership
    Group Address    Interface                Uptime    Expires   Last Reporter   Group Accounted        GigabitEthernet0/1       19:22:56  00:01:07

    Can you explain
    Why the host cannot see cant see here

  4. There are two options that come to mind:

    R1#show ip multicast                   
            Multicast Routing: enabled
            Multicast Multipath: disabled
            Multicast Route limit: No limit
            Multicast Triggered RPF check: enabled
            Multicast Fallback group mode: Sparse
            Multicast DVMRP Interoperability: disabled

    Or just check the running config:

    R1#show run | include multicast-routing
    ip multicast-routing

  5. Hello Recto

    The to range of multicast IP addresses known as “Administratively scoped” addresses. These are defined by RFC 2365 and are reserved for private use within an organization. So to answer your question, yes, when configuring multicast groups it is best practice to use these addresses.

    Having said that, as you probably know, there are various special-use multicast addresses that have various purposes as defined by the IANA and by various RFCs. Although I don’t like linking to Wikipedia, I find that their summary of the IPv4

    ... Continue reading in our forum

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