Certainly! Router-on-a-Stick is a technique used to enable inter-VLAN routing using a single physical link between a router and a switch. Let's walk through the steps to configure it:
1. Create VLANs on the Switch (S1):
- Create VLAN 10 and VLAN 30 on S1:
```
S1(config)# vlan 10 S1(config-vlan)# name LAN10 S1(config-vlan)# exit S1(config)# vlan 30 S1(config-vlan)# name LAN30 S1(config-vlan)# exit ```
2. Assign VLANs to Ports:
- Configure interfaces F0/6 and F0/11 as access ports and assign VLANs:
```
S1(config)# interface f0/11 S1(config-if)# switchport mode access S1(config-if)# switchport access vlan 10 S1(config-if)# interface f0/6 S1(config-if)# switchport mode access S1(config-if)# switchport access vlan 30 ```
3. Test Connectivity:
- Verify that PC1 and PC3 can ping each other. If not, remember that they are on different IP networks and require a router or Layer 3 switch for communication.
4. Configure Subinterfaces on R1 (Router):
- Create subinterfaces on R1 using 802.1Q encapsulation:
```
R1(config)# interface g0/0.10 R1(config-subif)# encapsulation dot1Q 10 R1(config-subif)# ip address 172.17.10.1 255.255.255.0 R1(config-subif)# interface g0/0.30 R1(config-subif)# encapsulation dot1Q 30 R1(config-subif)# ip address 172.17.30.1 255.255.255.0 ```
5. Verify Configuration:
- Use the `show ip interface brief` command to verify subinterface configuration.
Remember that router-on-a-stick allows routing between VLANs by logically dividing the router interface into subinterfaces, each associated with a specific VLAN. Trunk links between switches and the router are essential for forwarding traffic within and between VLANs. ๐๐
![Router-on-a-Stick Topology](https://www.ciscopress.com/articles/article.asp?p=3089357&seqNum=5)