1. 1 Inter-VLAN routing Chapter 6 CCNA Exploration Semester 3 Modified by Profs. Ward and Cappellino

2. 2 Topics Routing network traffic between VLANs Configuring a router for routing between VLANs Troubleshoot inter-VLAN connectivity issues

3. 3 Semester 3 LAN DesignBasic Switch Concepts VLANs VTP STP Inter-VLAN routing- Ch 6 Wireless

4. 4 Inter VLAN routing Switch keeps VLANs separate _________________ _______________ Router can _____________ ____________________ allows devices connected to different VLANs to communicate Inter-VLAN routing is a __________________________ _______________________________________________

5. 5 __________ inter-VLAN routing The router and switch both have __________________________________ ___________________ of the router has an _________________________________ Routing is the same as routing between any subnets. See next slide for example…

6. 6 Traditional inter-VLAN routing PC1 has a packet for 192.168.2.19 – different subnet ARP request to find MAC address of default gateway Send packet to F0/0 of router Router looks up 192.168.2.0 network – port F0/1 Router sends out packet through F0/1 to switchport F0/2 Switchport F0/2 is on VLAN30 and forwards to PC3. 1. 4. 3. 2.

7. 7 Inter-VLAN routing using ____________________ What about creating a trunk link to the router? A _______________ ___________________ ___________________

8. 8 Inter-VLAN routing using Router-on-a-Stick cont… "Router-on-a-stick" is a type of router configuration in which __________________ ____________________________________ ________________________________ The _____________ is configured to operate as a _____________ and is connected to a ________ _____________________________ Each VLAN needs a different IP address. Use ____________, each with its own IP address.  Subinterfaces are multiple ______________, associated with ____________________________

9. 9 Router-on-a-Stick cont… R1 F0/0 has subinterfaces, one for each VLAN. Each has its own IP address. VLAN tags on trunk.

10. 10 Availability of trunking Not all routers allow subinterfaces for VLAN trunking on Ethernet ports. It depends on the IOS feature set.

11. 11 Router Interface Configuration Recall how to program an IP address on a router’s interface? In which configuration mode is this done? To overcome the hardware limitations of inter-VLAN routing based on router physical interfaces…

12. 12 _________________ are used A subinterface is _________________________________ _________________________________________ Subinterface is represented by: the _______________ followed by __________________________ It is normal to _______________________. If this ties in with the IP address, even better. Ex: interface f0/0.10 Might be associated with subnet 192.17.10.0 Each subinterface has it own IP address. The physical interface has no IP address The ________________________________ Issue the “no shutdown” command Then ____ subinterfaces off that physical interface are enabled

13. 13 Configuring subinterfaces R1(config)#interface f0/0.10 R1(config-subif)#encapsulation dot1q 10 R1(config-subif)#ip address 172.17.10.1 255.255.255.0 (add any other subinterfaces) R1(config-subif)#interface f0/0 R1(config-if)#no shutdown

14. 14 Routing table Subinterfaces are shown

15. 15 Router Interface vs. Subinterface

16. 16 Configuration When configuring Inter-VLAN routing, the _______ ________________, _____________________ Switch configuration Create VLANs VLANs assigned to the switch ports For Router-on-a-stick configuration, _________________ Router configuration Configure interfaces (__________ for Router-on-a-stick) including ip addresses, encapsulation, no shutdown etc Use _______ commands, ping and tracert to verify

17. 17 Troubleshooting Check physical connections Check switchport VLAN assigment Check trunking on switches Check IP addressing and subnetting scheme in relation to VLANs Check router subinterface configuration