Wednesday, April 13, 2011

assign ip to the l3 switch ethernet port

l3>en
l3#config t
l3#int Gi0/0/20
l3#no switchport
l3#ip address 10.10.10.5 255.255.255.252
l3#

ip is assigned to the port of the l3 switch

Monday, April 11, 2011

BGP (BORDER GATEWAY PROTOCOL

1. BGP is IGP or EGP?
2. BGP is link state or distance vector protocol?
3. BGP uses which port?
4. When to use BGP?
5. Can I use BGP instead of any IGP?
6. Can I run two BGP process on single router?
7. What is Autonomous System?
8. Types of BGP routing table?
9. What is the BGP path selection criteria?
10. Define various BGP path attributes.
11. Why weight doesn’t fall under path attribute category?
12. What is confederation?
13. What is route reflector and why it is required?
14. What is no-synchronization rule?
15. Default BGP timers.
16. When does BGP use 0.0.0.0 router id?
17. Does route reflector come in actual path during traffic forwarding?
18. What is Site of origin aka SOO?
19. What is the cost of external and internal BGP routes?
20. Can we use local preference outside the autonomous system?
21. Does it require that BGP router-id should reachable in cloud?
22. What is recursive lookup in BGP and how it works?
23. What is the meaning of update source loopback?
24. If a static route is advertised in BGP without using update source what will be the next hop address in update?
25. Define various types of communities and why they are used?
26. If BGP neighbor state is showing idle what does it mean?
27. In Multihoming scenario if primary link gets fail, after how long traffic will be shifted to secondary link.
28. I am having two routes for remote destination but only single route is installing in routing table, what’s the reason for this?
29. How many links can be assigned for load balancing or sharing?
30. In eBGP I am establishing my neighbourship with loopback address but it’s not coming up. Please specify different reasons for not coming up.
31. Can we redistribute BGP in IGP? Please explain your answers.
32. What is cluster id?
33. I am receiving updates from eBGP peer, will the next hop change or not?
34. I am receiving updates from iBGP peer, will the next hop change or not?
35. A router is receiving same route from two different eBGP peers. The AS information contains in peer 1 is {65500, 65550, 65555} and in peer 2 is {65501, 65501}. But I want to make peer 1 preferred.
36. What is the difference between next-hop-self and update source loopback?
37. Define loop prevention mechanism in BGP.