CCNA RSE Lab: 6.3.3.7 Configuring 802.1Q Trunk-Based Inter-VLAN Routing

CCNA RSE Lab: 6.3.3.7 Configuring 802.1Q Trunk-Based Inter-VLAN Routing

Topology

Addressing Table

Switch Port Assignment Specifications

Ports Assignment Networ
S1 F0/1 802.1 Q Trunk N/A
S2 F0/1 802.1Q Trunk N/A
S1 F0/5 802.1 Q Trunk N/A
S1 F0/6 VLAN 10 – Students 192.168.10.0/24
S2 F0/18 VLAN 20 – Faculty 192.168.20.0/24

Objectives
Part 1: Build the Network and Configure Basic Device Settings
Part 2: Configure Switches with VLANs and Trunking
Part 3: Configure Trunk-Based Inter-VLAN Routing

Background / Scenario
A second method of providing routing and connectivity for multiple VLANs is through the use of an 802.1Q trunk between one or more switches and a single router interface. This method is also known as router-on-astick inter-VLAN routing. In this method, the physical router interface is divided into multiple subinterfaces that provide logical pathways to all VLANs connected.

In this lab, you will configure trunk-based inter-VLAN routing and verify connectivity to hosts on different VLANs as well as with a loopback on the router.

Note: This lab provides minimal assistance with the actual commands necessary to configure trunk-based inter-VLAN routing. However, the required configuration commands are provided in Appendix A of this lab. Test your knowledge by trying to configure the devices without referring to the appendix.

Note: The routers used with CCNA hands-on labs are Cisco 1 941 Integrated Services Routers (ISRs) with Cisco IOS, Release 1 5.2(4)M3 (universalk9 image). The switches used are Cisco Catalyst 2960s with Cisco IOS, Release 1 5.0(2) (lanbasek9 image). Other routers, switches and Cisco IOS versions can be used. Depending on the model and Cisco IOS version, the commands available and output produced might vary from what is shown in the labs. Refer to the Router Interface Summary Table at the end of the lab for the correct interface identifiers.

Note: Make sure that the routers and switches have been erased and have no startup configurations. If you are unsure, contact your instructor.

Instructor Note: Refer to the Instructor Lab Manual for the procedures to initialize and reload devices.

Required Resources

  • 1 Router (Cisco 1941 with Cisco IOS, release 15.2(4)M3 universal image or comparable)
  • 2 Switches (Cisco 2960 with Cisco IOS, release 15.0(2) lanbasek9 image or comparable)
  • 2 PCs (Windows 7, Vista, or XP with terminal emulation program, such as Tera Term)
  • Console cables to configure the Cisco IOS devices via the console ports
  • Ethernet cables as shown in the topology
Part 1: Build the Network and Configure Basic Device Settings

In Part 1, you will set up the network topology and configure basic settings on the PC hosts, switches, and router.

Step 1: Cable the network as shown in the topology.
Step 2: Configure PC hosts.
Step 3: Initialize and reload the router and switches as necessary.
Step 4: Configure basic settings for each switch.
a. Console into the switch and enter global configuration mode.
b. Copy the following basic configuration and paste it to the running-configuration on the switch.

c. Configure the device name as shown in the topology.
d. Configure the IP address listed in the Addressing Table for VLAN 1 on the switch.
e. Configure the default gateway on the switch.
f. Administratively deactivate all unused ports on the switch.
g. Copy the running configuration to the startup configuration.

Step 5: Configure basic settings for the router.
a. Console into the router and enter global configuration mode.
b. Copy the following basic configuration and paste it to the running-configuration on the router.

c. Configure the Lo0 IP address as shown in the Address Table. Do not configure sub-interfaces at this time. They will be configured in Part 3.
d. Copy the running configuration to the startup configuration.

Part 2: Configure Switches with VLANs and Trunking

In Part 2, you will configure the switches with VLANs and trunking.

Note: The required commands for Part 2 are provided in Appendix A. Test your knowledge by trying to configure S1 and S2 without referring to the appendix.

Step 1: Configure VLANs on S1 .
a. On S1, configure the VLANs and names listed in the Switch Port Assignment Specifications table. Write the commands you used in the space provided.

b. On S1, configure the interface connected to R1 as a trunk. Also configure the interface connected to S2 as a trunk. Write the commands you used in the space provided.

c. On S1, assign the access port for PC-A to VLAN 10. Write the commands you used in the space provided.

Step 2: Configure VLANs on Switch 2.
a. On S2, configure the VLANs and names listed in the Switch Port Assignment Specifications table.
b. On S2, verify that the VLAN names and numbers match those on S1 . Write the command you used in the space provided.

c. On S2, assign the access port for PC-B to VLAN 20.
d. On S2, configure the interface connected to S1 as a trunk.

Part 3: Configure Trunk-Based Inter-VLAN Routing

In Part 3, you will configure R1 to route to multiple VLANs by creating subinterfaces for each VLAN. This method of inter-VLAN routing is called router-on-a-stick.

Note: The required commands for Part 3 are provided in Appendix A. Test your knowledge by trying to configure trunk-based or router-on-a-stick inter-VLAN routing without referring to the appendix.

Step 1: Configure a subinterface for VLAN 1 .
a. Create a subinterface on R1 G0/1 for VLAN 1 using 1 as the subinterface ID. Write the command you used in the space provided.

b. Configure the subinterface to operate on VLAN 1 . Write the command you used in the space provided.

c. Configure the subinterface with the IP address from the Address Table. Write the command you used in the space provided.

Step 2: Configure a subinterface for VLAN 1 0.
a. Create a subinterface on R1 G0/1 for VLAN 10 using 1 0 as the subinterface ID.
b. Configure the subinterface to operate on VLAN 1 0.
c. Configure the subinterface with the address from the Address Table.

Step 3: Configure a subinterface for VLAN 20.
a. Create a subinterface on R1 G0/1 for VLAN 20 using 20 as the subinterface ID.
b. Configure the subinterface to operate on VLAN 20.
c. Configure the subinterface with the address from the Address Table.

Step 4: Enable the G0/1 interface.
Enable the G0/1 interface. Write the commands you used in the space provided.

Step 5: Verify connectivity.
Enter the command to view the routing table on R1 . What networks are listed?
192.168.1.0, 192.168.10.0, 192.168.20.0, and 209.165.200.224

If the answer is no to any of these questions, troubleshoot the configurations and correct any errors.

Reflection
What are the advantages of trunk-based or router-on-a-stick inter-VLAN routing?
Router-on-a-stick inter-VLAN routing allows for one interface to route to multiple VLANs unlike the legacy inter-VLAN method which requires one port per VLAN

Router Interface Summary Table

Router Interface Summary

Router Model Ethernet Interface #1 Ethernet Interface #2 Serial Interface #1 Serial Interface #2
1800 Fast Ethernet 0/0
(F0/0)
Fast Ethernet 0/1
(F0/1)
Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1)
1900 Gigabit Ethernet 0/0
(G0/0)
Gigabit Ethernet 0/1
(G0/1)
Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1)
2801 Fast Ethernet 0/0
(F0/0)
Fast Ethernet 0/1
(F0/1)
Serial 0/1 /0 (S0/1 /0) Serial 0/1 /1 (S0/1 /1)
2811 Fast Ethernet 0/0
(F0/0)
Fast Ethernet 0/1
(F0/1)
Serial 0/0/0 (S0/0/0) Serial 0/0/1 (S0/0/1)
2900 Gigabit Ethernet 0/0 (G0/0) Gigabit Ethernet 0/1 (G0/1) Serial 0/0/0(S0/0/0) Serial 0/0/1 (S0/0/1)
Note: To find out how the router is configured, look at the interfaces to identify the type of router and how many interfaces the router has. There is no way to effectively list all the combinations of configurations for each router class. This table includes identifiers for the possible combinations of Ethernet and Serial interfaces in the device. The table does not include any other type of interface, even though a specific router may contain one. An example of this might be an ISDN BRI interface. The string in parenthesis is the legal abbreviation that can be used in Cisco IOS commands to represent the interface.

Appendix A – Configuration Commands

Switch S1

Switch S2

Router R1

Device Configs
Instructor Note: The VLANs configured do not display in the switch running configuration but are stored in the vlan.dat file. The output from the show vlan brief command is provided.

Router R1

Switch S1

Switch S2

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