Distance vector routing protocols like RIP use hop count as the metric to determine the best path. This can lead to routing loops when routers continuously update each other with increasing hop counts, a problem known as "counting to infinity". RIP implements techniques like split horizon, holddown timers, and triggered updates to prevent this. The document goes on to describe how to configure and verify RIP, troubleshoot routing issues, and integrate static routes. It also provides an overview of IGRP configuration and verification.

1. DISTANCE VECTOR ROUTING TS, PHẠM VĂN TÍNH PART11

2. Objective Describe how routing loops can occur in distance vector routing Describe several methods used by distance vector routing protocols to ensure that routing information is accurate Configure RIP Use the ip classless command Troubleshoot RIP Configure RIP for load balancing Configure static routes for RIP Verify RIP Configure IGRP Verify IGRP operation Troubleshoot IGRP

3. Distance Vector Concepts

4. Distance Vector Network Discovery

5. Distance vector topology change

6. Distance vector routing loop

7. Problem : Counting to Infinity

8. Solution: Defining a maximum count

9. Solution: Split Horizon

10. Solution : Holddown Timers

11. R outing I nformation P rotocol

12. RIP It is a distance-vector routing protocol. Hop count is used as the metric for path selection. If the hop count is greater than 15, the packet will be discarded. By default, routing updates are broadcast every 30 seconds. RIP implements split horizon and holddown mechanisms to prevent incorrect routing information from being propagated ( Loop )

13. Configuring RIP BHM(config)# router rip – Selects RIP as the routing protocol BHM(config-router)# network 10.0.0.0 BHM(config-router)# network 192.168.13.0 – Specifies a directly connected networks

14. Common RIP configuration issues To reduce routing loops and counting to infinity, RIP uses the following techniques: Count-to-infinity Split horizon Holddown counters Triggered updates GAD(config-if)# no ip split-horizon Router(config-router)# timers basic update invalid holddown flush GAD(config-router)# update-timer seconds GAD(config-router)# passive-interface s0/0

15. Verifying RIP configuration

16. Verifying RIP configuration

17. Verifying RIP configuration BHM(config)# show ip route BHM(config)# show ip protocols BHM(config)# show running-config BHM(config)# show interface s0/0 BHM(config)# show ip interface s0/0

18. Troubleshooting RIP update issues BHM(config)# debug ip rip Other commands to troubleshoot RIP: show ip rip database show ip protocols {summary} show ip route debug ip rip {events} show ip interface brief

19. Preventing routing updates through an interface

20. Integrating static routes with RIP GAD(config-router)# redistribute static

21. I nterior G ateway R outing P rotocol

22. IGRP Metrics: - bandwidth - delay

23. IGRP : Show ip route

24. Configuring IGRP

25. IGRP : Timers Update timer : 90 s Invalid timer : 270 s Holddown timer : 280 s Flush timer : 630 s

26. Verifying IGRP configuration show ip route show interface interface show running-config show running-config interface interface show ip protocols debug ip igrp events debug ip igrp transactions