Let us establish a baseline topology for Cisco Lab 162:
| Device | Interface | IP Address | Connected To | | :--- | :--- | :--- | :--- | | PC1 | NIC | 192.168.10.2/24 | SW1 (Fa0/1) – VLAN 10 | | PC2 | NIC | 192.168.10.3/24 | SW2 (Fa0/2) – VLAN 10 | | PC3 | NIC | 192.168.20.2/24 | SW1 (Fa0/2) – VLAN 20 | | PC4 | NIC | 192.168.20.3/24 | SW2 (Fa0/3) – VLAN 20 | | Multilayer SW | VLAN 10 SVI | 192.168.10.1/24 | Trunk to SW1 & SW2 | | Multilayer SW | VLAN 20 SVI | 192.168.20.1/24 | Trunk to SW1 & SW2 |
Note: Your specific lab manual may use different IP ranges (e.g., 172.16.10.0), but the logic remains identical.
Before we touch the router, we must prepare the switching infrastructure. We need to create the VLANs and assign the access ports. cisco+lab+162
1. Create VLANs and Name Them:
S1> enable
S1# configure terminal
S1(config)# vlan 10
S1(config-vlan)# name Sales
S1(config-vlan)# exit
S1(config)# vlan 20
S1(config-vlan)# Name Engineering
S1(config-vlan)# exit
2. Configure Access Interfaces:
Connect the PCs to the switch and assign the ports to the correct VLANs. Let's assume PC1 is on interface FastEthernet0/1 and PC2 is on FastEthernet0/2.
S1(config)# interface fa0/1
S1(config-if)# switchport mode access
S1(config-if)# switchport access vlan 10
S1(config-if)# no shutdown
S1(config)# interface fa0/2
S1(config-if)# switchport mode access
S1(config-if)# switchport access vlan 20
S1(config-if)# no shutdown
3. Configure the Trunk Interface:
The link connecting the Switch to the Router must be a trunk to carry traffic for both VLAN 10 and 20. Let's assume the uplink is GigabitEthernet0/1. Let us establish a baseline topology for Cisco
S1(config)# interface gi0/1
S1(config-if)# switchport mode trunk
S1(config-if)# no shutdown
Now comes the moment of truth. Let’s verify that our configuration works.
1. Verify Router Interfaces: Check if the sub-interfaces are "up/up" and have the correct IPs.
R1# show ip interface brief
You should see g0/0.10 and g0/0.20 with status "up". but subsequent pings should succeed.
2. Verify Trunking on Switch: Ensure the link to the router is indeed trunking.
S1# show interfaces trunk
You should see VLANs 10 and 20 allowed on the trunk.
3. The Ping Test: From PC1, attempt to ping PC2.
C:\> ping 192.168.20.10
If the ping is successful (replies received), congratulations! You have successfully configured Inter-VLAN routing. The first ping might time out due to ARP processes, but subsequent pings should succeed.