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OSPF Questions 2

May 9th, 2017 Go to comments

Question 1

Explanation

In IPv6, you can configure many address prefixes on an interface. In OSPFv3, all address prefixes on an interface are included by default. You cannot select some address prefixes to be imported into OSPFv3; either all address prefixes on an interface are imported, or no address prefixes on an interface are imported.

Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_ospf/configuration/15-sy/iro-15-sy-book/ip6-route-ospfv3.html

Question 3

Question 4

Explanation

Because the destination of 172.16.1.1 is not present in the routing table so this router would use the default route (O*E2) to forward this packet. Usually the O*E2 is the result of the “default-information originate” command on the upstream router.

Question 5

Question 6

Explanation

Before we can implement OSPFv3 we need to configure an IPv4 router ID (although OSPFv3 deals with IPv6 addresses, it still uses 32-bit router ID) on that device and enable IPv6 unicast routing (via the “ipv6 unicast-routing” in global configuration mode).

Note: If we have already had an active interface, we don’t need to configure the router ID for OSPFv3 anymore because the device will automatically choose that IPv4 address for its router ID).

Question 7

Question 8

Explanation

Hierarchical design of OSPF (basically means that you can separate the larger internetwork into smaller internetworks called areas) helps us create a network with all features listed above (decrease routing overhead, speed up convergence, confine network instability to single areas of the network).

Comments (1) Comments
  1. nickaro
    September 12th, 2017

    In Q4 192.168.1.1 is included in route 192.168.0.0/16. So packets are sent to 192.168.15.5 out interface Fa1/1. Am I right?

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