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EIGRP Questions 2

July 27th, 2017 in ROUTE 300-101 Go to comments

Question 1


The “eigrp stub” command is equivalent to the “eigrp stub connected summary” command which advertises the connected routes and summarized routes.

Note: Summary routes can be created manually with the summary address command or automatically at a major network border router with the auto-summary command enabled.

Question 2

Question 3

Question 4

Note: Maybe SATx is the name of a router

Question 5


If an older version of code is deployed on the hub router, it will ignore the stub TLV and continue to send QUERY packets to the stub router. However, the stub router will immediately reply “inaccessible” to any QUERY packets, and will not continue to propagate them. Thus, the solution is backward-compatible and does not necessarily require an upgrade on the hub routers.

Reference: http://www.cisco.com/en/US/technologies/tk648/tk365/technologies_white_paper0900aecd8023df6f.html

Question 6

Question 7


To become a neighbor, the following conditions must be met:
+ The router must hear a Hello packet from a neighbor.
+ The EIGRP autonomous system (AS) must be the same.
+ K-values must be the same.

Question 8

Question 9

Question 10


Below is an example of the “show ip eigrp neighbors” output.


Let’s analyze these columns:

+ H: lists the neighbors in the order this router was learned
+ Address: the IP address of the neighbors
+ Interface: the interface of the local router on which this Hello packet was received
+ Hold (sec): the amount of time left before neighbor is considered in “down” status
+ Uptime: amount of time since the adjacency was established
+ SRTT (Smooth Round Trip Timer): the average time in milliseconds between the transmission of a packet to a neighbor and the receipt of an acknowledgement.
+ RTO (Retransmission Timeout): if a multicast has failed, then a unicast is sent to that particular router, the RTO is the time in milliseconds that the router waits for an acknowledgement of that unicast.
+ Queue count (Q Cnt): shows the number of queued EIGRP packets. It is usually 0.
+ Sequence Number (Seq Num): the sequence number of the last update EIGRP packet received. Each update message is given a sequence number, and the received ACK should have the same sequence number. The next update message to that neighbor will use Seq Num + 1.

In this question we have to check the RTO and Q cnt fields.

Question 11


By default, EIGRP uses only the bandwidth & delay parameters to calculate the metric (metric = bandwidth + delay). In particular, EIGRP uses the slowest bandwidth of the outgoing interfaces of the route to calculate the metric as follows:


For an example of how EIGRP calculates the metric, please read our EIGRP tutorial (part 3).

Question 12

Question 13

  1. Pif
    August 5th, 2017

    Please where I can find the questions for these answers ?

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