CCNA IP Routing Practice Test 19 — 15 Questions

Question 1

You are connected to R1 via console. The network administrator has attempted to configure OSPFv2 between R1, R2, and R3 but OSPF neighbor adjacencies are failing. Configure R1 to correct all issues so that R1 becomes FULL neighbors with both R2 and R3. Do not modify any other device's configuration.

Accepted Answer

Add 'no passive-interface GigabitEthernet0/0' and 'no passive-interface GigabitEthernet0/1' under OSPF configuration, but keep 'passive-interface default'.. The core issue is that R1 has 'passive-interface default' under the OSPF process, which prevents all interfaces from sending or receiving OSPF hello packets, breaking neighbor formation. The correct fix is to override this default with 'no passive-interface' on the interfaces that connect to neighbors (GigabitEthernet0/0 and GigabitEthernet0/1), allowing OSPF to form adjacencies while keeping other interfaces passive for security. Option B matches the solution commands and is the intended approach. Option A would also work but removes the default entirely, potentially enabling OSPF on all interfaces, which is not the recommended best practice in this scenario.

Answer

Remove the 'passive-interface default' command and remove the 'passive-interface GigabitEthernet0/0' and 'passive-interface GigabitEthernet0/1' commands under OSPF configuration.

Answer

Change the network statements to include the correct wildcard masks for the subnets on GigabitEthernet0/0 and GigabitEthernet0/1.

Answer

Add 'ip ospf network point-to-point' on both GigabitEthernet0/0 and GigabitEthernet0/1 interfaces.

Question 2

You are connected to R1. R1, R2, and R3 are connected via serial links as shown. Configure single-area OSPFv2 on all three routers so that all interfaces in the 10.0.0.0/8 range participate in OSPF area 0, except the loopback interfaces. Currently R1 cannot form OSPF adjacencies with R2 and R3. Examine the running-config of R1 below and determine the corrective actions needed.

Accepted Answer

Remove the passive-interface configuration from GigabitEthernet0/0, Serial0/0/0, and Serial0/0/1, and adjust the hello timer on Serial0/0/0 to 30 seconds.. R1 has passive-interface configured on all active interfaces (G0/0, Se0/0/0, Se0/0/1), which prevents OSPF hello packets from being sent and stops adjacencies from forming. Additionally, the hello timer on Serial0/0/0 is mismatched (default 10 vs. required 30). To resolve the adjacency issues while keeping loopback interfaces inactive, the passive-interface command must be removed from only the necessary interfaces and the hello timer on Se0/0/0 must be set to 30 seconds.

Answer

Change the OSPF network type on all interfaces to point-to-point and increase the dead timer to 120 seconds.

Answer

Add the network 10.0.0.0 0.255.255.255 area 0 command under router ospf and enable OSPF on all interfaces.

Answer

Configure the loopback interfaces with the ip ospf network point-to-point command to ensure they participate in OSPF.

Question 3

You are connected to R1 via console. R1 and R2 are directly connected via GigabitEthernet0/0. Configure OSPF process 1 on both routers so that they form a full adjacency. R1's router-id must be 1.1.1.1, and R2's router-id must be 2.2.2.2. Use network statements to advertise the direct link. Ensure that R1 does not send OSPF hellos out of its GigabitEthernet0/1 interface. The current configuration on R1 has mismatched hello and dead timers, and an incorrect network type, preventing adjacency. Fix all issues.

Accepted Answer

On R1, configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' under interface GigabitEthernet0/0, and ensure network type is broadcast. On R2, configure 'router-id 2.2.2.2' under router ospf 1. Also, on R1, add 'passive-interface GigabitEthernet0/1' under router ospf 1.. The adjacency was failing because R1 had incorrect hello (30) and dead (120) timers, while R2 used defaults (10/40). Additionally, R1’s network type was set to a non-broadcast type, causing a mismatch. To fix, on R1’s GigabitEthernet0/0, set hello-interval 10, dead-interval 40, and network type broadcast. In OSPF process 1 on R1, configure passive-interface GigabitEthernet0/1 to suppress hellos on that interface. On R2, under router ospf 1, set router-id 2.2.2.2. Option A addresses all requirements. Option B uses wrong timers and passive-interface default, which blocks hellos on all interfaces, breaking adjacency. Option C sets network type point-to-point, creating a type mismatch with R2’s broadcast, preventing adjacency. Option D omits the passive-interface command, failing to suppress hellos on GigabitEthernet0/1 as required.

Answer

On R1, configure 'ip ospf hello-interval 30' and 'ip ospf dead-interval 120' under interface GigabitEthernet0/0, and set network type to point-to-point. On R2, configure 'router-id 2.2.2.2' under router ospf 1. Also, on R1, add 'passive-interface default' under router ospf 1.

Answer

On R1, configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' under interface GigabitEthernet0/0, and set network type to point-to-point. On R2, configure 'router-id 2.2.2.2' under router ospf 1. Also, on R1, add 'passive-interface GigabitEthernet0/1' under router ospf 1.

Answer

On R1, configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' under interface GigabitEthernet0/0, and ensure network type is broadcast. On R2, configure 'router-id 2.2.2.2' under router ospf 1. Also, on R1, add 'network 10.0.0.0 0.255.255.255 area 0' under router ospf 1.

Question 4

You have console access to both R1 and R2. Configure OSPFv2 on both routers to establish a single-area adjacency in area 0. The link between R1 and R2 uses 10.0.0.0/30. Currently, OSPF is not configured on either router. After configuration, verify the adjacency forms and routes are exchanged.

Accepted Answer

Configure 'router ospf 1' on R1 and R2, set router-id, and use 'network 10.0.0.0 0.0.0.3 area 0' on both routers.. The essential requirement is enabling OSPFv2 on both routers with matching area 0 on the 10.0.0.0/30 link. On R1 and R2, enter 'router ospf 1', set a unique router-id, and use 'network 10.0.0.0 0.0.0.3 area 0' to advertise the link. The solution commands include optional networks (192.168.1.0/24 and Loopback0) that are not required for the adjacency and are shown only as examples; candidates should focus on the link network. After configuration, 'show ip ospf neighbor' should show a FULL state. Common mistakes include using a subnet mask instead of a wildcard mask (option C) or a /32 wildcard (option D), and not configuring OSPF on R2 (option B).

Answer

Configure 'router ospf 1' on R1 only, and use 'network 10.0.0.0 0.0.0.3 area 0' on R1; R2 does not need OSPF configuration because it will learn routes via the directly connected interface.

Answer

Configure 'router ospf 1' on both routers, set router-id, and use 'network 10.0.0.0 255.255.255.252 area 0' on both routers.

Answer

Configure 'router ospf 1' on both routers, set router-id, and use 'network 10.0.0.0 0.0.0.0 area 0' on both routers.

Question 5

You are connected to R1. R1 has OSPF configured on GigabitEthernet0/0 with network 10.0.0.0 0.0.0.3 area 1, ip ospf hello-interval 10, and ip ospf dead-interval 40. R2 has OSPF configured on its GigabitEthernet0/0 with network 10.0.0.0 0.0.0.3 area 0, ip ospf hello-interval 5, and ip ospf dead-interval 20. Correct these mismatches so that R1 and R2 become OSPF neighbors.

Accepted Answer

On R1, change the network statement to area 0 and set ip ospf hello-interval 5 and ip ospf dead-interval 20 under the interface.. The OSPF adjacency fails due to two mismatches. First, the area is mismatched: R1 uses area 1, R2 uses area 0 (both must be the same area, typically area 0). Second, the hello and dead timers are mismatched: R1 uses Hello 10/Dead 40, R2 uses Hello 5/Dead 20. To fix, on R1 change the network statement to area 0 and adjust timers to match R2 (or vice versa). The solution below changes R1's area to 0 and sets hello to 5 and dead to 20 to match R2.

Answer

On R2, change the network statement to area 1 and set ip ospf hello-interval 10 and ip ospf dead-interval 40 under the interface.

Answer

On R1, change the network statement to area 0 and set ip ospf hello-interval 10 and ip ospf dead-interval 40 under the interface.

Answer

On R2, change the network statement to area 0 and set ip ospf hello-interval 10 and ip ospf dead-interval 40 under the interface.

Question 6

You are connected to R1 via the console. Configure OSPFv2 on R1 and R2 to establish a single-area OSPF adjacency in area 0. The link between R1 (G0/0) and R2 (G0/0) uses 10.0.0.0/30, and both routers must use an MTU of 1500. The current configuration has mismatched hello/dead timers and an area mismatch, preventing adjacency. Fix all issues so that R1 and R2 become fully adjacent.

Accepted Answer

On R1, change the network statement to area 0 and set the hello interval to 5 under interface G0/0.. The adjacency fails because of two mismatches: the OSPF area on R1 is area 1 while R2 uses area 0, and the hello/dead timers differ (R1: 10/40, R2: 5/20). To fix, on R1 change the network statement to area 0 and adjust the hello interval to 5 (which also automatically sets dead to 20). Option B is wrong because it places the adjacency in area 1 (not area 0) and does not fix the timer mismatch on R2. Option C is wrong because it does not address the hello/dead timer mismatch; the MTU is already correct at 1500. Option D is wrong because it leaves the hello interval mismatched (10 vs 5) and alters the dead interval unnecessarily; the dead interval is automatically derived from the hello interval.

Answer

On R2, change the network statement to area 1 and set the hello interval to 10 under interface G0/0.

Answer

On R1, change the network statement to area 0 and set the MTU to 1500 under interface G0/0.

Answer

On R2, change the network statement to area 0 and set the dead interval to 40 under interface G0/0.

Question 7

You are connected to R1. Configure single-area OSPFv2 on R1 and R2 so that they become fully adjacent. The link between them is 10.0.0.0/30, with R1 using G0/0 and R2 using G0/1. The current configuration has mismatched hello/dead timers: R1's G0/0 uses hello 10 and dead 40, while R2's G0/1 uses hello 30 and dead 120. Also, the 'passive-interface loopback0' command is missing on R1. Ensure OSPF is enabled in area 0, use router-id 1.1.1.1 on R1 and 2.2.2.2 on R2, and correct the timer mismatch.

Accepted Answer

On R2, configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' under G0/1. On R1, configure 'passive-interface loopback0' under router ospf.. The adjacency fails because R2's G0/1 has hello/dead timers of 30/120, while R1's G0/0 uses 10/40. To fix, on R2 under interface G0/1, use 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40'. Additionally, R1's loopback0 is advertised via a /32 network statement but should be made passive to prevent OSPF hellos from being sent out (where no neighbor exists). On R1, configure 'passive-interface loopback0' under router ospf. After both changes, adjacency forms.

Answer

On R1, configure 'ip ospf hello-interval 30' and 'ip ospf dead-interval 120' under G0/0. On R2, configure 'passive-interface loopback0' under router ospf.

Answer

On R1, configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' under G0/0. On R2, configure 'passive-interface loopback0' under router ospf.

Answer

On R2, configure 'ip ospf hello-interval 30' and 'ip ospf dead-interval 120' under G0/1. On R1, configure 'passive-interface loopback0' under router ospf.

Question 8

You are connected to R1 via the console. Configure single-area OSPFv2 on R1, R2, and R3 so that all three routers can exchange routes. The current configuration has mismatched hello/dead timers on the link between R1 and R2, and an area mismatch on the link between R2 and R3. Correct these issues and ensure OSPF adjacencies form.

Accepted Answer

On R2, configure interface G0/0 with 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40', and modify the OSPF network statement for 10.0.23.0/30 to area 0.. The adjacency between R1 and R2 fails because R1 has hello/dead timers of 10/40, while R2 has 30/120 on G0/0. The adjacency between R2 and R3 fails because R2's G0/1 is in area 1, but R3's G0/1 is in area 0. On R2, change the hello/dead timers on G0/0 to match R1 (10/40) using 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40'. Also change the network statement for 10.0.23.0/30 to area 0 using 'network 10.0.23.0 0.0.0.3 area 0'. Verify with 'show ip ospf neighbor' on all routers.

Answer

On R2, configure interface G0/0 with 'ip ospf hello-interval 30' and 'ip ospf dead-interval 120', and modify the OSPF network statement for 10.0.23.0/30 to area 1.

Answer

On R1, configure interface G0/0 with 'ip ospf hello-interval 30' and 'ip ospf dead-interval 120', and on R3, change the OSPF network statement for 10.0.23.0/30 to area 1.

Answer

On R1, configure interface G0/0 with 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40', and on R2, modify the OSPF network statement for 10.0.23.0/30 to area 1.

Question 9

You are connected to R1. Configure OSPFv2 on R1 and R2 so that they form a full adjacency and can exchange routes. The current configuration has mismatched hello/dead timers blocking the adjacency. Adjust only the necessary settings on R1 to match R2's OSPF timers.

Accepted Answer

Configure 'ip ospf hello-interval 5' and 'ip ospf dead-interval 20' on R1's GigabitEthernet0/0 interface.. The adjacency between R1 and R2 is not forming because the OSPF hello and dead timers are mismatched. R1 has default timers (Hello 10, Dead 40) while R2 has custom timers (Hello 5, Dead 20). To form an adjacency, OSPF timers must match on both ends. On R1, you need to configure the OSPF interface timers to match R2 by issuing 'ip ospf hello-interval 5' and 'ip ospf dead-interval 20' on interface GigabitEthernet0/0. After applying these commands, the adjacency should come up.

Answer

Configure 'ip ospf hello-interval 10' and 'ip ospf dead-interval 40' on R2's interface to match R1's default timers.

Answer

Configure 'ip ospf hello-interval 5' on R1's GigabitEthernet0/0 interface only; the dead interval will adjust automatically.

Answer

Configure 'ip ospf dead-interval 20' on R1's GigabitEthernet0/0 interface only; the hello interval will adjust automatically.

Question 10

You are connected to R1 via console. You have attempted to configure single-area OSPFv2 on R1 and R2 so that they form a full adjacency, but the adjacency is not establishing. The link between them is 192.168.1.0/30. R1 uses G0/0 (192.168.1.1/30) and R2 uses G0/0 (192.168.1.2/30). R1's router-id must be 1.1.1.1, and R2's router-id must be 2.2.2.2. Additionally, ensure that no OSPF hello packets are sent on R1's loopback0 interface (10.0.0.1/32). After troubleshooting, identify what is causing the issue and what must be corrected. Then verify the adjacency is full and passive-interface is set correctly.

Accepted Answer

The adjacency is not forming because the hello and dead timers are mismatched: R1 uses Hello 10 / Dead 40, but R2 uses Hello 5 / Dead 20. To fix, on R1's G0/0 interface, change the hello timer to 5 and dead timer to 20 using 'ip ospf hello-interval 5' and 'ip ospf dead-interval 20' (or adjust R2 to match R1's timers). After correction, the adjacency should become full. Additionally, R1's loopback0 is already correctly configured as passive-interface.. The correct answer is A: the adjacency is not forming because the hello and dead timers are mismatched. R1 uses Hello 10 / Dead 40, while R2 uses Hello 5 / Dead 20. To fix, on R1's G0/0 interface, change the hello timer to 5 and dead timer to 20 using 'ip ospf hello-interval 5' and 'ip ospf dead-interval 20' (or adjust R2 to match R1's timers). After correction, the adjacency becomes full. The other options are incorrect: B is wrong because router-ids can be set after the process starts and a mismatch does not prevent adjacency; C is wrong because network type mismatch would still allow adjacency if both agree (or if one is point-to-point and the other broadcast they will not form, but that is not the case here); D is wrong because the passive-interface on G0/0 would prevent hello packets and thus adjacency, but the question states it is only on loopback0, so that is not the issue. Verify with 'show ip ospf neighbor' and 'show ip ospf interface loopback0'.

Answer

The adjacency is not forming because R1's router-id is not set correctly. To fix, configure 'router-id 1.1.1.1' under the OSPF process on R1, and 'router-id 2.2.2.2' on R2. After that, clear the OSPF process with 'clear ip ospf process' to force the new router-id to take effect. Additionally, R1's loopback0 is already correctly configured as passive-interface.

Answer

The adjacency is not forming because the network type is mismatched: R1 is configured as point-to-point, while R2 is broadcast. To fix, change the network type on both interfaces to the same type, e.g., 'ip ospf network point-to-point' on both. Additionally, R1's loopback0 is already correctly configured as passive-interface.

Answer

The adjacency is not forming because the passive-interface command is incorrectly applied to R1's G0/0 interface instead of loopback0. To fix, remove passive-interface from G0/0 using 'no passive-interface g0/0' and ensure it is only applied to loopback0. Additionally, verify that the router-ids are correctly set.

Question 11

You are connected to R1 via console. R1 and R2 are directly connected via their GigabitEthernet0/0 interfaces. Configure OSPFv3 for IPv6 on both routers so that the loopback0 interface on R2 (with IPv6 address 2001:db8:acad:2::1/64) is reachable from R1. Enable IPv6 unicast routing, enable OSPFv3 on the appropriate interfaces, and verify the neighbor adjacency and routing table. (Note: R2 already has OSPFv3 configured and is waiting for R1 to complete its configuration.)

Accepted Answer

Enable IPv6 unicast routing, configure OSPFv3 process with router-id, enable OSPFv3 on GigabitEthernet0/0 in area 0, and verify neighbor and route.. The issue is that OSPFv3 process is not enabled on R1. To fix, first ensure IPv6 unicast routing is enabled (already done). Then configure OSPFv3 routing process with a process ID (e.g., 1) and router-id using the `ipv6 router ospf 1` command and `router-id` command. Then enable OSPFv3 on the GigabitEthernet0/0 interface with `ipv6 ospf 1 area 0`. Finally, verify with `show ospfv3 neighbor` to see R2's router ID (e.g., 2.2.2.2) and `show ipv6 route ospf` to see the route to 2001:db8:acad:2::/64.

Answer

Enable IPv6 unicast routing, configure OSPFv2 process with router-id, enable OSPFv2 on GigabitEthernet0/0 in area 0, and verify neighbor and route.

Answer

Enable IPv6 unicast routing, configure OSPFv3 process without a router-id, enable OSPFv3 on GigabitEthernet0/0 in area 0, and verify neighbor and route.

Answer

Enable IPv6 unicast routing, configure OSPFv3 process with router-id, enable OSPFv3 on GigabitEthernet0/0 in area 0, but do not verify neighbor or route.

Question 12

You are connected to R1, a router that must establish OSPFv3 adjacency with R2 over the directly connected link G0/0. The current configuration is incomplete: OSPFv3 process is configured but not enabled on the interface, and global IPv6 unicast routing is missing. Configure R1 so that it becomes an OSPFv3 neighbor with R2 and learns the loopback route 2001:db8:1:2::/64 via OSPFv3. Then verify neighbor state and routing table.

Accepted Answer

Enable IPv6 unicast routing globally and activate OSPFv3 on GigabitEthernet0/0 with the command 'ipv6 ospf 1 area 0'.. R1 is missing two critical configurations: global IPv6 unicast routing must be enabled with 'ipv6 unicast-routing', and OSPFv3 must be activated on GigabitEthernet0/0 using 'ipv6 ospf 1 area 0' under the interface. Without these, R1 cannot send or receive OSPFv3 hellos, so no adjacency forms and routes are not exchanged. After applying both commands, the neighbor state becomes FULL and the remote loopback appears in the IPv6 routing table.

Answer

Enable IPv6 unicast routing globally and configure OSPFv3 process 1 with the 'network' command under the OSPFv3 router configuration mode.

Answer

Enable IPv6 unicast routing globally and configure OSPFv3 process 1 with the 'router-id' command to ensure adjacency.

Answer

Enable IPv6 unicast routing globally and configure OSPFv3 process 1 with the 'passive-interface default' command to allow adjacency.

Question 13

You are connected to R1, a Cisco router that must establish OSPFv3 adjacency with R2 over its GigabitEthernet0/0 link. The link uses IPv6 addresses 2001:db8:1:1::1/64 on R1 and 2001:db8:1:1::2/64 on R2. R1 currently has IPv6 unicast routing enabled but no OSPFv3 process configured. Configure R1 so that it forms a full OSPFv3 neighbor relationship with R2 and installs the loopback network 2001:db8:2:2::/64 (advertised by R2) into its IPv6 routing table.

Accepted Answer

ipv6 router ospf 1
router-id 1.1.1.1
interface GigabitEthernet0/0
 ipv6 ospf 1 area 0. R1 requires OSPFv3 configuration: enable the process with 'ipv6 router ospf 1', set a router-id, then enable OSPFv3 on the interface with 'ipv6 ospf 1 area 0'. Option B incorrectly attempts to use a network command (OSPFv2 syntax). Option C sets a point-to-point network type, which on a broadcast link will mismatch with R2's default broadcast type and prevent adjacency. Option D changes the hello interval to 5, causing a timer mismatch and adjacency failure.

Answer

ipv6 router ospf 1
router-id 1.1.1.1
interface GigabitEthernet0/0
 ipv6 ospf 1 area 0
 network 2001:db8:1:1::0/64 area 0

Answer

ipv6 router ospf 1
router-id 1.1.1.1
interface GigabitEthernet0/0
 ipv6 ospf 1 area 0
 ipv6 ospf network point-to-point

Answer

ipv6 router ospf 1
router-id 1.1.1.1
interface GigabitEthernet0/0
 ipv6 ospf 1 area 0
 ipv6 ospf hello-interval 5

Question 14

You are connected to R1 via console. Configure OSPFv3 for IPv6 on R1 and R2 so that IPv6 loopback interfaces on both routers can communicate. R1's GigabitEthernet0/0 and R2's GigabitEthernet0/1 are directly connected. Ensure OSPFv3 is enabled on the correct interfaces and verify neighbors and routes.

Accepted Answer

Enable OSPFv3 on R1's GigabitEthernet0/0 and Loopback0, and on R2's GigabitEthernet0/1 and Loopback0.. The issue is that OSPFv3 is not enabled on the interfaces. On R1, OSPFv3 must be enabled on GigabitEthernet0/0 (the link to R2) and Loopback0 (to advertise the loopback). On R2, OSPFv3 must be enabled on GigabitEthernet0/1 (the link to R1) and Loopback0. After enabling OSPFv3 on the correct interfaces, the neighbor adjacency forms and routes are exchanged.

Answer

Enable OSPFv3 only on the loopback interfaces of both routers.

Answer

Enable OSPFv3 on R1's GigabitEthernet0/0 and R2's GigabitEthernet0/1 only, without loopbacks.

Answer

Enable OSPFv3 on R1's Loopback0 and R2's GigabitEthernet0/1 only.

Question 15

You are connected to R1. Configure OSPFv3 for IPv6 on R1 and R2 so that the loopback0 interface on R1 (IPv6 address 2001:db8:1::1/64) can ping the loopback0 interface on R2 (IPv6 address 2001:db8:2::1/64). The routers are connected via their GigabitEthernet0/0 interfaces using IPv6 addresses 2001:db8:12::1/64 (R1) and 2001:db8:12::2/64 (R2). OSPFv3 process ID 100 must be used, and all interfaces must be in area 0.

Accepted Answer

R1(config)# ipv6 unicast-routing
R1(config)# ipv6 router ospf 100
R1(config-rtr)# router-id 1.1.1.1
R1(config-rtr)# interface gigabitethernet0/0
R1(config-if)# ipv6 ospf 100 area 0
R1(config-if)# interface loopback0
R1(config-if)# ipv6 ospf 100 area 0

R2(config)# ipv6 unicast-routing
R2(config)# ipv6 router ospf 100
R2(config-rtr)# router-id 2.2.2.2
R2(config-rtr)# interface gigabitethernet0/0
R2(config-if)# ipv6 ospf 100 area 0
R2(config-if)# interface loopback0
R2(config-if)# ipv6 ospf 100 area 0. OSPFv3 for IPv6 requires enabling IPv6 unicast routing globally and configuring OSPFv3 on interfaces. The missing step was enabling OSPFv3 process 100 and assigning area 0 to the interfaces. On R1, the commands 'ipv6 router ospf 100' and 'router-id 1.1.1.1' create the OSPFv3 process, then 'ipv6 ospf 100 area 0' under each interface enables OSPFv3 on those interfaces. Similar commands on R2 with a unique router-id complete the configuration. Verification with 'show ospfv3 neighbor' should show R2's router-id, and 'show ipv6 route ospf' should display the remote loopback network.

Answer

R1(config)# ipv6 unicast-routing
R1(config)# ipv6 router ospf 100
R1(config-rtr)# router-id 1.1.1.1
R1(config-rtr)# network 2001:db8:12::0/64 area 0
R1(config-rtr)# network 2001:db8:1::0/64 area 0

R2(config)# ipv6 unicast-routing
R2(config)# ipv6 router ospf 100
R2(config-rtr)# router-id 2.2.2.2
R2(config-rtr)# network 2001:db8:12::0/64 area 0
R2(config-rtr)# network 2001:db8:2::0/64 area 0

Answer

R1(config)# ipv6 unicast-routing
R1(config)# ipv6 router ospf 100
R1(config-rtr)# router-id 1.1.1.1
R1(config-rtr)# interface gigabitethernet0/0
R1(config-if)# ipv6 ospf 100 area 0

R2(config)# ipv6 unicast-routing
R2(config)# ipv6 router ospf 100
R2(config-rtr)# router-id 2.2.2.2
R2(config-rtr)# interface gigabitethernet0/0
R2(config-if)# ipv6 ospf 100 area 0

Answer

R1(config)# ipv6 unicast-routing
R1(config)# ipv6 router ospf 100
R1(config-rtr)# router-id 1.1.1.1
R1(config-rtr)# interface gigabitethernet0/0
R1(config-if)# ipv6 ospf 100 area 0
R1(config-if)# interface loopback0
R1(config-if)# ipv6 ospf 100 area 0

R2(config)# ipv6 unicast-routing
R2(config)# ipv6 router ospf 100
R2(config-rtr)# router-id 1.1.1.1
R2(config-rtr)# interface gigabitethernet0/0
R2(config-if)# ipv6 ospf 100 area 0
R2(config-if)# interface loopback0
R2(config-if)# ipv6 ospf 100 area 0