8.23

•Configure the designated IGMP querier on the VLAN 146 segment so that failed multicast traffic receivers are detected and removed within 60 seconds.

In the config it states "In real life, you would configure every router on the segment with the same settings, but this task’s goal is to check your understanding of the querier election".

However what appears misleading to me is in the output for "sh ip igmp int f0/0 on R1" you see:

IGMP querier timeout is 40 seconds

But the task stated "removed within 60s".  Was anything below 60s ok?  (I specifically set it to 60s).

Comments

  •  

    However what appears misleading to me is in the output for "sh ip igmp int f0/0 on R1" you see:

    IGMP querier timeout is 40 seconds

    R1 win the election as the querier because it has the lowest ip address over the multicast segment.

    Now keepin this in mind R1 is the querier and it is supposed to send periodic query to verify the membership reports answer coming from multicast subscribers. Since the query-interval has an maximum holdtime of 3Xquery-interval when you set up the configuration of R1 you must account for this maximum period before the querier remove the membership of the igmp routers. So once you configure the timer of 20, when you multiplying this value to 3 you obtain the desired final timeout. The IGMP querier timeout specified in your request shouldn't be considered with regard of the querier in this case but instead should be configured over the others candidates queriers over the multicast segment (R4,R6) since that timer specifies the amount of time after which the actual querier is declared down. But have nothing to do with host membership reports.

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