Cisco 642-883 Free Practice Questions 2021

NEW QUESTION 1
An engineer wants to use an address family to configure internal BGP peer 10.1.1.1 as a route reflector client for unicast and multicast prefixes. Which option accomplishes this configuration?

• A. router bgp 140address-family ipv4 unicast neighbor 10.1.1.1remote-as 140address-family ipv4 unicast route-reflector-clientexitaddress-family ipv4 multicast route-reflector-client
• B. router bgp 140 neighbor 10.1.1.1address-family ipv4 unicast address-family ipv4 multicast remote-as 150route-reflector-client exit
• C. router bgp 140address-family ipv4 unicast route-reflector-clientaddress-family ipv4 multicast remote-as 140neighbor 10.1.1.1
• D. router bgp 140address-family ipv4 unicast neighbor 10.1.1.1remote-as 150address-family ipv4 unicast route-reflector-clientexitaddress-family ipv4 multicast route-reflector-client

Answer: A

NEW QUESTION 2
Refer to the PE1 router routing table output exhibit.

What is causing the i su 10.1.10.0/24 [115/30] via 0.0.0.0, 00:40:34, Null0 entry on the PE1 router routing table?

• A. The PE1 router is receiving the 10.1.10.0/24 summary route from the upstream L1/L2 IS-IS router.
• B. The PE1 router has been configured to summarize the 10.1.10.x/32 IS-IS routes to 10.1.10.0/24.
• C. The 10.1.10.0/24 has been suppressed because IS-IS auto-summary has been disabled on the PE1 router.
• D. The 10.1.10.0/24 has been suppressed because of a route policy configuration on the PE1 router.
• E. The 10.1.10.0/24 has been suppressed because the more specific 10.1.10.x/32 IS-IS routes have been configured to leak into the IS-IS non-backbone area.

Answer: B

Explanation:
C:Documents and Settingsuser-nwzDesktop1.JPG

NEW QUESTION 3
Which option is an invalid BGP community representation?

• A. binary
• B. autonomous system number : value
• C. hexadecimal
• D. decimal

Answer: C

NEW QUESTION 4
Which value must be configured when redistributing OSPFv2 into RIP?

• A. metric
• B. bandwidth
• C. delay
• D. MTU
• E. reliability

Answer: A

NEW QUESTION 5
Which two of the following are true regarding the BGP Prefix-Based outbound route filtering feature? (Choose two.)

• A. IP multicast routes are not supported.
• B. Outbound route filtering is configured only on a per-address family basis.
• C. Outbound route filtering can be configured for either iBGP or eBGP sessions.
• D. The outbound route filter can be defined in a Prefix list, Distribute list or Access lists.
• E. Outbound route filtering is more effective when a distance vector IGP is used.

Answer: AB

Explanation: http://www.cisco.com/en/US/docs/ios/12_2s/feature/guide/fsbgporf.pdf
Restrictions for BGP Prefix-Based Outbound Route Filtering
• The BGP Prefix-Based Outbound Route Filtering feature does not support IP multicast routes.
• IP addresses that are used for outbound route filtering must be defined in an IP prefix-list. BGP distribute lists and IP access lists are not supported.
• Outbound route filtering is configured on only a per-address family basis and cannot be configured under the general session or BGP routing process (Router(config-router)#).
• Outbound route filtering is configured for only external peering sessions.

NEW QUESTION 6
Which AS path access list is used by a multihomed customer to only announce their own address space to their service providers to prevent the multihomed customer from becoming a transit AS?

• A. ip as-path access-list permit.*
• B. ip as-path access-list permit^$
• C. ip as-path access-list permit _$
• D. ip as-path access-list permit _^
• E. ip as-path access-list permit local-as ip as-path access-list deny *
• F. ip as-path access-list deny.* ip as-path access-list permit *

Answer: B

Explanation:
C:Documents and Settingsuser-nwzDesktop1.JPG

NEW QUESTION 7
Which two unique attributes are used for the loop prevention mechanism when route reflectors are deployed in a network? (Choose two.)

• A. local preference
• B. originator-ID
• C. AS-path
• D. next-hop
• E. origin
• F. cluster-list

Answer: BE

NEW QUESTION 8
Which statement is correct regarding the DR election process In this OSPF implementation?

• A. Both the CE5 and PE6 routers are DROTHERs
• B. PE5 is the OSPFv2 DR for the GigabitEthernet link between PE5 and PE6
• C. PE6 is the OSPFv2 and OSPFv3 DR for the GigabitEthernet link between PE5 and PE6
• D. PE6 is the DR for the GigabitEthernet link between PE5 and PE6 because it has a higher OSPF priority

Answer: A

Explanation: # show ip ospf neighbor
# show ipv6 ospf neighbor

NEW QUESTION 9
Refer to the exhibit.

Which configuration on XR2 provides R1 with only the minimum routing information to reach the rest of the network?

• A. Router isis ABCinterface GigabitEthernet0/0/0/1 circuit-type level-2-only
• B. Router isis ABCinterface GigabitEthernet0/0/0/0 circuit-type level-1-2
• C. Router isis ABCinterface GigabitEthernet0/0/0/1 circuit-type level-1
• D. Router isis ABCinterface GigabitEthernet0/0/0/0 circuit-type level-1

Answer: D

NEW QUESTION 10
Refer to the Cisco IOS XR route policy exhibit.

If the original incoming routing update has an MED of 10 and a local preference of 100, how will the routing update be modified?

• A. The local preference will be set to 100, the MED will be set to 10, and the weight will be set to 100.
• B. The local preference will be set to 100, the MED will be set to 10, and the weight will be set to 200.
• C. The local preference will be set to 200, the MED will be set to 10, and the weight will be set to 100.
• D. The local preference will be set to 200, the MED will be set to 10, and the weight will be set to 200.

Answer: C

NEW QUESTION 11
Which option is a tool that is used to ensure that BGP AS does not become a transit AS?

• A. as-path filter-list
• B. local-preference
• C. ttl-security
• D. confederations

Answer: A

NEW QUESTION 12
What are two characteristics of the multihomed customers to service providers connection option? (Choose two.)

• A. Multihomed customers must use a private AS number.
• B. The traffic load can be shared for different destination networks between service providers.
• C. Multihomed customers must receive a full routing table from the service providers.
• D. The routing methodology must be capable of reacting to dynamic change
• E. BGP is used to achieve this flexibility.
• F. Multihomed customers must use a provider-assigned address space.

Answer: BD

NEW QUESTION 13
What is the default OSPF seed metric and type?

• A. 10 and E1
• B. 10 and E2
• C. 20 and E1
• D. 20 and E2
• E. 0 and E1
• F. 0 and E2

Answer: D

NEW QUESTION 14
Referring to the partial Cisco IOS-XR BGP configuration exhibit, when trying to commit this configuration, the following error is displayed:
% Failed to commit one or more configuration items during a pseudo-atomic operation. All changes made have been reverted. Please issue 'show configuration failed' from this session to view the errors.

What is wrong with the configuration?

• A. IPv6 unicast routing has not been enabled globally using the ipv6 unicast-routing command
• B. The configuration is missing the required network command
• C. The update-source loopback 0 commands must be configured under the respective neighbor address-family
• D. The configuration is missing the address-family ipv4 unicast and address-family ipv6unicast commands under router bgp 65111

Answer: D

NEW QUESTION 15
Refer to the IS-IS configuration exhibit.

This is the typical IS-IS configuration of the routers in an AS using IS-IS as the IGP. This AS is in the transition phase of integrating IPv6 into the network. During this transition phase, some of the routers within the AS might be running IPv4 only, some might be running IPv6 only, and others might be running both IPv4 and IPv6. To avoid any black holes for the IPv6 traffic, which configuration change can be made?

• A. Disable IS-IS adjacency checks.
• B. Enable IPv6 adjacency over IPv4 IS-IS peering.
• C. Enable multi-topology IS-IS.
• D. Disable the IPv4 unicast address-family.
• E. Enable IS-IS wide metric to support the single-topology mode.

Answer: C

NEW QUESTION 16
Why would a network engineer want to implement BGP peer groups on Cisco IOS XE routers?

• A. to have a single point of configuration for all route maps used with BGP
• B. to have a single point of configuration for neighbors with the same BGP policies
• C. to have a single point of configuration for all global BGP configurations
• D. to have a single point of configuration for all Layer 3 VPN customer VRFs

Answer: B

NEW QUESTION 17
The S bit in the MPLS header is used for what purpose?

• A. To indicate the bottom level in the label stack
• B. To indicate if LDP is sync to the IGP
• C. To indicate if LDP is sync to the IGP
• D. To indicate the status of the LSP

Answer: A

Explanation:
C:Documents and Settingsuser-nwzDesktop1.JPG
a 1-bit bottom of stack flag. If this is set, it signifies that the current label is the last in the stack.

NEW QUESTION 18
When redistributing routes into OSPF, which kind of routes will be redistributed by default on Cisco IOS XR Software but will not be automatically redistributed by default on Cisco IOS Software and Cisco IOS XE Software?

• A. Type 1 external routes
• B. Type 2 external routes
• C. subnetted routes
• D. /32 host routes
• E. tagged static routes

Answer: C

Explanation:
C:Documents and Settingsuser-nwzDesktop1.JPG

NEW QUESTION 19
In a Cisco IOS XR OSPF NSF operation, which option is the result of a segment without NSF-capable peers?

• A. NSF is disabled on all segmentson any linecard that has a non-NSF-capable neighbor.
• B. NSF capabilities for that segment are disabled.
• C. NSF operates in unidirectional mode for that segment.
• D. NSF is disabled globally on the router.

Answer: B