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IS-IS Protocol Configuration - Class Guide

The following overall topology is used for the below labs.

Overall Topology

IP Addressing

IP addressing is already configured for all labs.

Lab 1: Configure IS-IS as a Single Flood Domain

Lab 1 uses the following topology:

Lab 1 Topology

Preparing The Lab

  1. Log into the LabAccess jumpserver:
    1. Type labs to get to the Additional Labs menu.
    2. Type isis-lab-guide in order to get to the ISIS Lab Guide labs.
    3. Type lab1 in this menu in order to begin deploying configurations for this lab.
    4. Wait until you are prompted that the lab deployment is complete. This will take some time.

Lab Tasks

  1. Configure EOS1 to EOS6 links to be in a single area and flood domain:

    1. Enable ipv4 routing.
    2. Use area 0000.
    3. Use IS-IS Instance name of 1.
    4. Match the system-id of each device to the name of the device. (1)

      1. Eg. EOS1’s last system-id hextet will be 0001 and EOS6’s will be 0006
    5. Advertise all loopbacks.

    6. Ensure there are no pseudonodes in the environment.
  2. All intermediate systems should have all routes from other intermediate systems.

  3. All intermediate system loopbacks should be able to reach each other.
  4. Look at the isis database details:

    1. Are there any pseudonodes? If so, why?
    2. Are there multiple link state databases? If so, why?
    3. Make note of reachability information. What types of reachability are being advertised?
  5. Look at the routing table and make a note of what it looks like currently.

    1. How many routes are there in the show ip route summary?

Lab 2: Loopback Only Advertisements in LSPs

Lab 2 uses the following topology:

Lab 2 Topology

Preparing The Lab

Note

If you are continuing from Lab 1, you can skip these steps and go directly to Lab Tasks.

  1. Log into the LabAccess jumpserver:
    1. Type labs to get to the Additional Labs menu.
    2. Type isis-lab-guide in order to get to the ISIS Lab Guide labs.
    3. Type lab2 in this menu in order to begin deploying configurations for this lab.
    4. Wait until you are prompted that the lab deployment is complete. This will take some time.

Lab Tasks

  1. Configure IS-IS on EOS1 to EOS6 so that only loopback reachability is advertised in LSPs.

    1. Route maps should not be used.
  2. All intermediate systems should have only loopback routes from other intermediate systems.

  3. All intermediate system loopbacks should be able to reach each other.
  4. Look at the IS-IS database details:

    1. Make note of reachability information. What types of reachability are being advertised?
    2. How did this change from the last section?
  5. Look at the routing table and make a note of what it looks like currently:

    1. How many routes are there in the ‘show ip route summary?’
    2. How did the routing table change from the last section?

Lab 3: Broadcast Network

Lab 3 uses the following topology:

Lab 3 Topology

Preparing The Lab

Note

If you are continuing from Lab 2, you can skip these steps and go directly to Lab Tasks.

  1. Log into the LabAccess jumpserver:
    1. Type labs to get to the Additional Labs menu.
    2. Type isis-lab-guide in order to get to the ISIS Lab Guide labs.
    3. Type lab3 in this menu in order to begin deploying configurations for this lab.
    4. Wait until you are prompted that the lab deployment is complete. This will take some time.

Lab Tasks

  1. Configure IS-IS between EOS11, EOS12, and EOS13 using VLAN 100:

    1. Enable ipv4 routing
    2. Use area 0000
    3. Use ISIS Instance name of 1
    4. Continue using a single flood domain
    5. Match the system-id of each device to the name of the device (1)

      1. Eg. EOS11’s last system-id hextet will be 0011 and EOS13’s will be 0013.
  2. Advertise loopbacks into IS-IS.

  3. Only loopbacks should be advertised into the global routing table.
  4. Look at IS-IS neighbors:

    1. How many adjacencies do you have per device?
  5. Look at the IS-IS database:

    1. How does the IS-IS Database differ on the broadcast network?
    2. Are there any pseudonodes?
    3. If yes: How can you distinguish the pseudonode from other adjacencies?