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Cisco+lab+162

You will see lines like access-list 102 deny tcp 192.168.1.0 0.0.0.255 any eq 21.

In Part 1, you will connect to the router via the console and issue basic show commands to view the router's status.

Step 1: Connect to the router. a. Connect the PC to the router using a console cable. b. Open a terminal emulator program (such as PuTTY or TeraTerm). c. Press Enter to get the router prompt.

Step 2: Enter Privileged EXEC mode. a. At the user EXEC prompt (Router>), enter the enable command.

Router> enable
Router#

b. Notice the prompt changes from > to #, indicating you are in Privileged EXEC mode.

Step 3: Use the show version command. a. Enter the show version command to view system hardware and software status.

Router# show version

b. Question: What is the IOS version? (Answer varies based on the lab image, e.g., "Version 15.1(4)M") c. Question: What is the amount of total memory (RAM)? (Look for "xxxxxK/xxxxxK bytes of memory". The first number is Main Memory, the second is I/O Memory). d. Question: What is the Configuration Register setting? (Typically 0x2102). cisco+lab+162

Step 4: Use the show running-config command. a. Enter the command to view the currently running configuration.

Router# show running-config

b. Question: What is the hostname of the router? (Default is usually "Router"). c. Question: How many interfaces does the router have? (Look for lines starting with "interface". It usually lists GigabitEthernet or FastEthernet and Serial interfaces).

Step 5: Use the show ip interface brief command. This command is used to get a quick summary of the interface status. a. Enter the command:

Router# show ip interface brief

b. Observe the output columns: Interface, IP-Address, OK?, Method, Status, Protocol. c. Question: What is the status of the interfaces? (If no cables are connected, Status is usually "administratively down" or "down").

Step 6: Use the show interfaces command. a. Enter the command for a specific interface (e.g., G0/0 or Fa0/0).

Router# show interfaces gigabitethernet 0/0

b. Look for the line indicating the bandwidth (BW) and the MAC address (Hardware address). You will see lines like access-list 102 deny tcp 192

Without trunks, SW1’s VLAN 10 traffic cannot reach SW2’s VLAN 10. Trunks using IEEE 802.1Q add a VLAN tag to each frame.

On SW1 (uplink to Multilayer SW):

interface gigabitEthernet 0/1
 switchport trunk encapsulation dot1q   (Required on older switches)
 switchport mode trunk
 switchport trunk allowed vlan 10,20
 no shutdown

On SW2 (uplink to Multilayer SW):

interface gigabitEthernet 0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk allowed vlan 10,20
 no shutdown

Verification: Run show interfaces trunk. You should see the ports listed with Native VLAN "1" and allowed VLANs "10,20". If this output is blank, the trunk did not form—check for mismatched encapsulation or cabling.

This is the core of "Router-on-a-Stick." We will configure sub-interfaces on a single physical interface. Each sub-interface acts as the default gateway for a specific VLAN.

1. Enable the Physical Interface: Do not assign an IP address to the physical interface itself; just turn it on. PC2 (VLAN 20):

R1> enable
R1# configure terminal
R1(config)# interface gi0/0
R1(config-if)# no shutdown
R1(config-if)# exit

2. Configure Sub-Interface for VLAN 10: We create a logical interface gi0/0.10. We must specify the encapsulation (dot1q) and the VLAN ID (10).

R1(config)# interface gi0/0.10
R1(config-subif)# encapsulation dot1q 10
R1(config-subif)# ip address 192.168.10.1 255.255.255.0
R1(config-subif)# exit

3. Configure Sub-Interface for VLAN 20: Similarly, create gi0/0.20 for the Engineering VLAN.

R1(config)# interface gi0/0.20
R1(config-subif)# encapsulation dot1q 20
R1(config-subif)# ip address 192.168.20.1 255.255.255.0
R1(config-subif)# exit

Note: The IP addresses assigned here (.1) will be the Default Gateway addresses configured on your PCs.

(In a standard lab environment, there is typically one Router and one PC connected via Console cable. Sometimes a second Router is connected via Serial or Ethernet links to demonstrate neighbor connectivity.)

Don't forget to configure the PCs! A common mistake in Lab 1.6.2 is forgetting to set the gateway on the PCs.

  • PC2 (VLAN 20):