[magma] A question on multicast states in non-querier

Bharat Joshi <bharat_joshi@infosys.com> Mon, 14 February 2011 05:01 UTC

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From: Bharat Joshi <bharat_joshi@infosys.com>
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Date: Mon, 14 Feb 2011 10:31:40 +0530
Thread-Topic: A question on multicast states in non-querier
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Subject: [magma] A question on multicast states in non-querier
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Hi All,

      If there are two IGMP routers on a LAN, one of them gets elected as querier and another as non-querier.

      The querier sends query and hosts on that LAN reply with the reports. Querier sees those report and create a database. Non-querier also sees those report and would create the same database.

      Question is whether Multicast routing protocol running on non-querier's upstream interface should use this database to join/leave the multicast group or not?

      IIRC, it is required because the DR for that LAN could be the non-querier router and if we do not join upstream, multicast data won't flow to this router. Is this a correct thinking?

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