Cisco Certified Internetwork Expert – CCIE – Part 9

The CCIE Certification is the highest level of achievement for network professionals, certifying an individual as an expert or master. Cisco Systems has since become an unrivaled worldwide leader in networking for the Internet. Its networking solutions can easily connect users who work from diverse devices on disparate networks. Cisco products make it simple for people to access and transfer information without regard to differences in time, place, or platform.

The below listed questions are intended to help you continue on your exciting path toward obtaining your CCIE (Cisco Certified Internetwork Expert) certification. Before looking these questions, it is important to know the basic concepts of CCNA and CCNP.

1. Cisco Certified Internetwork Expert – CCIE – Part 1
2. Cisco Certified Internetwork Expert – CCIE – Part 2
3. Cisco Certified Internetwork Expert – CCIE – Part 3
4. Cisco Certified Internetwork Expert – CCIE – Part 4
5. Cisco Certified Internetwork Expert – CCIE – Part 5
6. Cisco Certified Internetwork Expert – CCIE – Part 6
7. Cisco Certified Internetwork Expert – CCIE – Part 7
8. Cisco Certified Internetwork Expert – CCIE – Part 8
9. Cisco Certified Internetwork Expert – CCIE – Part 9
10. Cisco Certified Internetwork Expert – CCIE – Part 10
11. Cisco Certified Internetwork Expert – CCIE – Part 11
12. Cisco Certified Internetwork Expert – CCIE – Part 12
13. Cisco Certified Internetwork Expert – CCIE – Part 13
14. Cisco Certified Internetwork Expert – CCIE – Part 14
15. Cisco Certified Internetwork Expert – CCIE – Part 15
16. Cisco Certified Internetwork Expert – CCIE – Part 16
17. Cisco Certified Internetwork Expert – CCIE – Part 17
18. Cisco Certified Internetwork Expert – CCIE – Part 18
19. Cisco Certified Internetwork Expert – CCIE – Part 19

These articles covers everything you need to pass the CCIE Routing and Switching written exam. Each article contains a set of testing questions along with their answer and explanation.

This article covers: Advanced BGP technology and configuration.

1. When should BGP be used? (Choose all that apply.)

1. When multi-homing
2. When connecting multiple ISPs
3. When connecting routers within the same AS
4. When configuring backup links

Answer – A, B
Explanation – BGP should be used when multi-homing and when connecting multiple ISPs.

2. When an autonomous system (AS) must traverse another autonomous system to get to its destination, the traversed autonomous system is called which of the following?

1. Transfer AS
2. Forwarding AS
3. Transit AS
4. Transmitting AS

Answer – C
Explanation – A transit AS is an autonomous system through which data from one autonomous system must travel to get to another autonomous system.

3. Which of the following describes an autonomous system between two other autonomous systems?

1. A middle AS
2. A stub AS
3. A transit AS
4. A transmitting AS
5. A non-transit AS

Answer – C
Explanation – A transit AS is an autonomous system through which data from one autonomous system must travel to get to another autonomous system. A stub AS is an autonomous system where the exit point and entry point are the same. A non-transit autonomous system is an autonomous system that does not pass data through to another autonomous system. There is no such thing as a transmitting or middle autonomous system.

4. The BGP hold timer is established in which of the following BGP message types?

1. OPEN
2. UPDATE
3. NOTIFICATION
4. KEEPALIVE

Answer – A
Explanation – The OPEN message is used to establish a connection between BGP peers and to negotiate the hold time. An UPDATE message is used to advertise topology updates and changes; a NOTIFICATION message is used to advertise errors; and a KEEPALIVE message type is sent to keep a session active when no UPDATE messages are exchanged during the established hold time.

5. If an external autonomous system is not receiving updates from your autonomous system, which of the following show commands can be used to troubleshoot this? (Choose all that apply.)

1. show ip bgp events
2. show ip bgp neighbor
3. show ip bgp all
4. show ip bgp

Answer – B, D
Explanation – The show ip bgp neighbor command displays all the advertised routes, and the show ip bgp command looks at all the connections.

6. When using debug commands with BGP, which of the following displays all the BGP events as they occur?

1. debug ip bgp dampening
2. debug ip bgp summary
3. debug ip bgp events
4. debug ip bgp all

Answer – C
Explanation – The debug ip bgp events command is used to display all BGP events as they occur. The only other valid command listed is debug ip bgp dampening.

7. Which of the following commands will begin a BGP process on a router and place you in BGP configuration mode?

1. router enable bgp
2. router ip bgp 45323
3. router bgp 32455
4. router enable bgp 34657

Answer – C
Explanation – The router bgp 32455 command is the only valid command listed to place the router in BGP configuration mode, which is identified by the (config-router) prompt.

8. Which of the following is the valid range of BGP ASNs?

1. 1 through 59,000
2. 1 through 65,535
3. 1 through 32,128
4. 1 through 65,012

Answer – B
Explanation – The valid range of BGP numbers is 1 through 65,535.

9. A grouping of BGP routers that share the same common policies is called which of the following?

1. Policy group
2. Peer group
3. Identi-Group
4. Access group

Answer – B
Explanation – Peer groups allow you to assign configurations to a group instead of to each individual router in a peer group.

10. The following output is an example of using which command?
BGP neighbor is 172.16.11.254, remote AS 100, internal
link
Index 1, Offset 0, Mask 0x2
Route-Reflector Client
BGP version 4, remote router ID 10.16.1.1
BGP state = Established, table version = 1, up for
12:10:16
Last read 00:00:06, hold time is 180,
keepalive interval is 60 seconds
Minimum time between advertisement runs is 5 seconds
Received 143 messages, 0 notifications, 0 in queue
Sent 52 messages, 0 notifications, 0 in queue
Prefix advertised , suppressed 0, withdrawn 0
Connections established 2; dropped 1
Last reset 12:10:16, due to User reset
53 accepted prefixes consume 32 bytes
0 history paths consume 0 bytes

1. show ip bgp all
2. show cdp bgp neighbors
3. show running-config
4. show ip bgp neighbors

Answer – D
Explanation – The show ip bgp neighbors command shows the configured BGP peers and the current connection status.

11. Which of the following commands can be used on a router when routes continuously flap to make sure that a link is up before it is advertised?

1. ip bgp as-path command
2. ip bgp hold time command
3. set as-path extended command
4. bgp dampening command

Answer – D
Explanation – The bgp dampening command is used by BGP to set a hold time before a route can be re-advertised.

12. Which of the following are multi-homing classifications for BGP? (Choose all that apply.)

1. Centralized
2. Basic
3. Medium
4. Full
5. Low

Answer – A, B, C
Explanation – Multi-homing with only static routes is considered a Basic classification; using static routes and BGP learned routes is considered a Medium classification; using only BGP learned routes is considered a Full classification.

13. Which command can be used to disable sequence numbering when creating prefix lists?

1. ip bgp prefix-list sequence-number disable
2. no ip bgp prefix-list sequence-number
3. disable ip bgp prefix-list sequence-number
4. no ip prefix-list

Answer – B
Explanation – The no ip bgp prefix-list sequence-number is used to disable sequence numbering for prefix lists. The only other real command is the no ip prefix-list, which is used to delete a prefix list.

14. BGP uses which of the following TCP ports to open a session with another BGP peer?

1. Port 20
2. Port 21
3. Port 179
4. Port 23

Answer – C
Explanation – Port 179 is used by BGP to establish a session with another BGP peer. Ports 20 and 21 are used by FTP, and port 23 is used by Telnet.

15. A route reflector not participating in a route reflector cluster is called which of the following?

1. Non-cluster client
2. Non-BGP router
3. Non-client
4. Non-iBGP client

Answer – C
Explanation – A router in a network that is running BGP but is not a participant in a route reflector cluster is referred to as a non-client router.