Cisco 642-883 Exam Questions 2021

NEW QUESTION 1
A service provider has set up new eBGP sessions for new customers who require Internet connectivity for their own public AS sessions. To connect, these sessions require MD5 authentication and no cluster ID configured. The NOC notified that one of these eBGP neighbors does not establish any session with the CE BGP speaker. Which option is a potential cause if the BGP configuration is correct?

• A. The BGPMD5 password has been typed incorrectly producing a failure in the authentication process.
• B. A public AS does not require another service provider to connect to the Interne
• C. The BGP configuration automatically blocks this type of design due to loop-avoidance built-in mechanisms.
• D. The customer BGP speaker is receiving too many prefixes at once and no connection can be established without a maximum –prefix value configured.
• E. No cluster ID is configured, so the BGP process does not find a way to identifythe service provider BGP speaker in the customer BGP route reflectors cluster-lis
• F. The session is not established to keep the customer iBGP core network loop-free.

Answer: A

NEW QUESTION 2
DRAG DROP

Answer:

Explanation: Matches the end of the AS Path String ---$ Matches the Start of the AS Path String ----^
Matches any single character --- . Matched any delimiter ---- -

NEW QUESTION 3
A Network Operation Center requires support to understand OSPFv3 neighborship operations. During a migration, two OSPFv3 routers became adjacent even though no common subnets were configured on the link interfaces. Which statement explains this problem?

• A. This problem is a bug in Cisco IOS XE, which requires a case tobe open with Cisco TAC and an immediate Cisco IOS upgrade to avoid security breaches and rerouting attacks.
• B. IPv6 needs only the link-local address to from an OSPFv3 neighborship.
• C. The Network Operation Center Engineers did not notice a supernet configured on one end of the IPv6 link.
• D. The Network Operation Center Engineers did not add the secondary keyword after the IPv6 address, which causes the router to overwrite the main address.

Answer: B

NEW QUESTION 4
An engineer has two routers multihomed to the Internet via BGP. The first should be the primary path for all outbound traffic and the second should automatically become active in the event the primary goes offline. Which method to configure the routers is the most simple?

• A. Set the local-preference to be higher on the primary router.
• B. Set the local-preference to be lower on the primary router.
• C. Set the MED to be higher on the primary router than the backup.
• D. Set the primary router to have a higher weight than the backup.

Answer: A

NEW QUESTION 5
On Cisco IOS XR Software, which set of commands is used to enable the gi0/0/0/1 interface for OSPF in area 0?

• A. interface gi0/0/0/0ip address 10.1.1.1 255.255.255.0!router ospf 1network 10.1.1.1 0.0.0.0 area 0
• B. interface gi0/0/0/0ip address 10.1.1.1 255.255.255.0!router ospf 1network 10.1.1.1 255.255.255.255 area 0
• C. router ospf 1 area 0interface GigabitEthernet0/0/0/1
• D. interface gi0/0/0/0ip address 10.1.1.1 255.255.255.0ip ospf 1 area 0
• E. router ospf 1address-family ipv4 unicastinterface GigabitEthernet0/0/0/1 area 0
• F. router ospf 1address-family ipv4 unicast interface GigabitEthernet0/0/0/1 area 0

Answer: C

NEW QUESTION 6
DRAG DROP

Answer:

Explanation: Totally Stubby Area – O,OIA , OE1 or OE2 types of OSPf routes NSSA Totally Stubby – O, and O*IA types of OSPF routes
Stubby OSPF Area - O, OIA and O*IA types of OSPF routes NSSA – O,OIA , ON1 or ON2 types of OSPF Routes

NEW QUESTION 7
You are implementing OSPF as the IGP using a single OSPF area design. The router
memory usage for OSPF is too high. Which two methods can lower the OSPF memory usage? (Choose two.)

• A. Enable OSPF synchronization
• B. Implement multi-area OSPF
• C. Enable OSPF sham links to reduce the number of LSAs
• D. Implement route summarization on the ABRs
• E. Enable route leaking between Level 1 and Level 2 areas

Answer: BD

NEW QUESTION 8
An engineer is working on routers within AS 100. Which regular expression can be used in an AS path access list to match locally originated routes from AS 100?

• A. ^100$
• B. ^$
• C. _100$
• D. ^[0-9]*$

Answer: B

NEW QUESTION 9
A network specialist is working for a large enterprise that has a BGP-enabled multihomed core infrastructure. Recently, the ISP that provides Internet connectivity to the company
had to temporarily disable one of the BGP sessions as a result of routers blackholing BGP prefixes in transit. Which option can the specialist use to avoid this incident in the future?

• A. filtering local prefixes outbound
• B. using only one router as primary BGP speaker
• C. permitting only local prefixes outbound
• D. filtering external prefixes inbound

Answer: C

NEW QUESTION 10
Which option is a mechanism that can be implemented between two eBGP peers to communicate the routes each peer needs from the other?

• A. ORF
• B. ACL
• C. prefix list
• D. route map

Answer: A

NEW QUESTION 11
Refer to the show command output in the exhibit.

For which reason will this router drop all traffic that is destined to the 1.1.1.0/24 network?

• A. The 1.1.1.0/24 route is not synchronized.
• B. The BGP next hop for reaching the 1.1.1.0/24 network is not reachable.
• C. The metric of the 1.1.1.0/24 route is set to 0.
• D. The weight of the 1.1.1.0/24 route is set to 0.
• E. The 1.1.1.0/24 route is an incomplete route.
• F. The IBGP split-horizon rule is preventing the router to use the IBGP route.

Answer: B

NEW QUESTION 12
An engineer is working for a service provider who is strategically important to the Internet data traffic. The CTO is promoting a core infrastructure upgrade to connect via optical links network service providers. Which three concerns must be addressed while planning the new BGP features and functionalities? (Choose three.)

• A. BGP suboptimal routing
• B. IPv4 exhaustion
• C. routers and switches hardware capabilities
• D. route dampening of current customers
• E. multihoming policies of new customers
• F. IGP reconvergence time on the inter-AS links
• G. BGP blackholing when acting as transit autonomous system

Answer: ACG

NEW QUESTION 13
For a Cisco IOS XR router, under which BGP configuration group can default-originate be added?

• A. session-group
• B. af-group
• C. neighbor-group
• D. peer-session template

Answer: B

NEW QUESTION 14
Which option can a network specialist use to configure connected route redistribution inside VRF "TEST" on Cisco IOS XR and allow only the prefix 10.10.10.0/24?

• A. route-policy ALLOW-CONNif destination in PERMIT_PREFIX then passelsedropend-policyprefix-set PERMIT_PREFIX 10.10.10.0/24end-setrouter bgp 65000 vrf TESTrd 65000:10000address-family ipv4 unicastredistribute connected route-policy ALLOW-CONN
• B. route-policy ALLOW-CONNif source in PERMIT_PREFIX then passelsedropend-policyprefix-set PERMIT_PREFIX 10.10.10.0/24end-setrouter bgp 65000 vrf TESTrd 65000:10000address-family ipv4 unicastredistribute connected route-policy ALLOW-CONN
• C. route-policy ALLOW-CONNif protocol is connected and source in PERMIT_PREFIX then passelsedropend-policyprefix-set PERMIT_PREFIX 10.10.10.0/24end-setrouter bgp 65000 vrf TESTrd 65000:10000address-family ipv4 unicastredistribute connected route-policy ALLOW-CONN"
• D. route-policy ALLOW-CONNif route-type is local and destination in PERMIT_PREFIX then passelsedropend-policyprefix-set PERMIT_PREFIX 10.10.10.0/24end-setrouter bgp 65000 vrf TESTrd 65000:10000address-family ipv4 unicastredistribute connected route-policy ALLOW-CONN

Answer: A

NEW QUESTION 15
Which option is where BGP graceful restart is negotiated between peers?

• A. open message
• B. keep-alive message
• C. notification message
• D. update message

Answer: A

NEW QUESTION 16
Refer to the exhibit.

Which Cisco IOS XE command should be added to this configuration for the BFD protocol to operate successfully?

• A. Router1(config-if)#bfd echoRouter2(config-if)#bfd echo
• B. Router1(config-ospf-ar-if)#bfd fast-detectRouter2(config-ospf-ar-if)#bfd fast-detect
• C. Router1(config-router)#bfd all-interfacesRouter2(config-router)#bfd all-interfaces
• D. Router1(config- bfd)#echo-enableRouter2(config- bfd)#echo-enable

Answer: C

NEW QUESTION 17
When using the show bgp ipv6 unicast summary command to verify the IPv6 BGP session status with the IPv6 BGP peers, you noticed the "St/PfxRcd" status for one of the IPv6 BGP peers is in the "Active" state. What does the "Active" state indicate?

• A. The IPv6 BGP session has been established with the IPv6 BGP peer.
• B. The router is in the process of sending BGP routing updates to the IPv6 BGP peer.
• C. The router is in the process of establishing the IPv6 BGP session with the IPv6 BGP peer.
• D. The router is exchanging BGP notification messages with its IPv6 BGP peer.

Answer: C

NEW QUESTION 18
Refer to the exhibit.

Which two configuration options can be used to optimize the IS-IS network scenario? (Choose two.)

• A. Change the R1 and R2 IS type to Level 2.
• B. Change the R1 and R2 IS type to Level 1.
• C. Change the gi0/0 interface IS-IS circuit type on R1 and R2 to Level 2 only.
• D. Change the gi0/1 interface IS-IS circuit type on R1and R2 to Level 1.
• E. Change the IS type for all the routers to Level-1-2.
• F. Change the IS-IS network type for all the routers to point-to-point.

Answer: CD

NEW QUESTION 19
An EIGRP domain is redistributed into an OSPF NSSA area. On which router would this redistribution occur?

• A. stub border router
• B. summary router
• C. autonomous system boundary router
• D. backbone router

Answer: C