This latest #CCNA CLI lab catches a variety of small items for OSPFv3 in an IPv6 network. Starting from a pre-configured set of routers with IPv6 addresses, this lab asks you to get OSPFv3 working, use specific router IDs, change the OSPF costs in a couple of different ways, and to change the number of equal-cost routes allowed in the IPv6 routing table. Check out the requirements below the fold!
Requirements
First, enable OSPFv3 in this network, a network for which the IPv6 addresses have already been configured. Additionally, you will further customize the OSPFv3 configuration, by changing the OSPFv3 interface costs in a couple of different ways, and setting the number of equal-cost routes allowed.
The specific rules for this lab are:
- Enable OSPFv3 on all the routers for all interfaces shown in the figure
- Place all interfaces in area 0
- Limit the maximum number of load-balanced paths on R1 to 1
- Directly configure the OSPFv3 cost on both ends of the link between R2 and R4 to a value of 10
- Indirectly configure the OSPFv3 on both ends of the link between R3 and R4 to a value of 10 by changing the link bandwidth
- Directly configure (without relying on interface IPv4 addresses) an obvious OSPFv3 router ID for each router, for instance, use 1.1.1.1 for router R1
Figure 1: Four Router with Unicast IPv6 Addresses
Initial Configuration
Examples 1, 2, 3 and 4 show the beginning configuration state of R1, R2, R3 and R4.
Example 1: R1 Config
hostname R1 ! ipv6 unicast-routing ! interface GigabitEthernet0/1 ipv6 address 2000::1/64 no shutdown ! interface GigabitEthernet0/2 ipv6 address 3000::1/64 no shutdown ! interface GigabitEthernet0/3 ipv6 address 2002::1/64 no shutdown
Example 2: R2 Config
hostname R2 ! ipv6 unicast-routing ! interface GigabitEthernet0/0 ipv6 address 2001::1/64 no shutdown ! interface GigabitEthernet0/1 ipv6 address 2000::2/64 no shutdown
Example 3: R3 Config
hostname R3 ! ipv6 unicast-routing ! interface GigabitEthernet0/0 ipv6 address 2003::1/64 no shutdown ! interface GigabitEthernet0/1 ipv6 address 2002::2/64 no shutdown
Example 4: R4 Config
ipv6 unicast-routing ! interface GigabitEthernet0/0 ipv6 address 3500::1/64 no shutdown ! interface GigabitEthernet0/1 ipv6 address 2001::2/64 no shutdown ! interface GigabitEthernet0/2 ipv6 address 2003::2/64 no shutdown
Answer on Paper, or Maybe Test in Lab
Create your own answer, either by typing it in somewhere, or writing it on paper. Try to avoid using your notes – one of points of these labs is to move you from being able to read someone else’s config to being able to create your own from scratch.
You can easily test this lab with a few show commands. First, each router should have two OSPFv3 neighbors (show ipv6 ospf neighbor). Then go to each router and check the OSPF cost on each interface (show ipv6 ospf interface brief). In this case, R1 and R4 should learn two equal-cost routes using OSPF for the subnets on the opposite side of the topology. If you configured correctly, R1 should list only one of those routes (to 3500::/64, with show ipv6 route), and R4 should list both routes (to 3000::/64, with show ipv6 route).