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Question 1 Selectable Answer

Which feature must be incorporated into the campus LAN design to enable Wake on LAN?

A. dynamic ARP Inspection Snooping on layer 2 devices
B. directed broadcasts on layer 3 devices
C. proxy ARP on layer 3 devices
D. DHCP Snooping on layer 2 devices

Answer:

Question 2 Written Answer

DRAG DROP
Drag and drop the steps WAN Edge performs when on-boarded into the Cisco SD-WAN overlay from the left into the order they are completed on the right.

Answer:

Explanation:
Table
Description automatically generated with low confidence

Question 3 Selectable Answer

Since installing a cisco TelePresence system, the company is experiencing other application having response issues when the system in use. As a result, the company asked an architect to recommend a QoS solution. The customer is currently using a CBWFQ policy to manage traffic on an internet connection with a speed of 100 Mbps.
Which link-capacity limit must the architect choose for strict-priority for the real-time traffic?

A. 25 Mbps
B. 50 Mbps
C. 33 Mbps
D. 75 Mbps

Answer:
Explanation:
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/qos_conmgt/configuration/xe-3s/qos-conmgt-xe-3s-book/qos-conmgt-oview.html#GUID-48F6AF58-5CCC-44A0-B868-125AE453FF2A%20%20%20%20%20%20(75%20Mbps)
The sum of all bandwidth allocation on an interface cannot exceed 75 percent of the total available interface bandwidth. The remaining 25 percent is used for other overhead, including Layer 2 overhead, routing traffic, and best-effort traffic. Bandwidth for the CBWFQ class-default class, for instance, is taken from the remaining 25 percent.

Question 4 Selectable Answer

Refer to the exhibit.

Area 10 is a regular OSPF area and networks 10.1.1.0/24 and 172.16.1.0/24 are internal.
Which design provides optimal routing between both networks when the link between routers C and E fails?

A. Move the link between routers C and D to area 10.
B. Create an OSPF virtual link between routers E and
C. Create a tunnel between routers E and F in area 10.
D. Make area 10 a not-so-stubby area.

Answer:

Question 5 Selectable Answer

Refer to the exhibit.

A customer is running HSRP on the core routers. Over time the company has grown and requires more
network capacity. In the current environment, some of the downstream interfaces are almost fully utilized, but others are not.
Which solution improves the situation?

A. Make router R2 active for half of the VLANs.
B. Add more interfaces to R1 and R2.
C. Configure port channel toward downstream switches.
D. Enable RSTP on the downstream switches.

Answer:

Question 6 Selectable Answer

Refer to the exhibit.

The distribution switches serve as the layer 3 boundary. HSRP preemption is enabled. When the primary switch comes back after a failure, traffic is initially dropped.
Which solution must be implemented to improve the design?

A. Increase the hello timers on both HSRP devices
B. Use the preempt delay feature on the primary HSRP device.
C. Use the preempt delay feature on the backup HSRP device
D. Configure a higher mac-refresh interval on both HSRP devices

Answer:

Question 7 Selectable Answer

An engineer must design a large Layer 2 domain that contains hundreds of switches and VLANs.
The engineer's primary goals are to:
• Efficiently utilize the bandwidth of all links
• Avoid Layer 2 loops
• Cause minimal impact on switch CPU and memory
Which technology should the engineer include in the design?

A. PVST+
B. Rapid PVST+
C. MST
D. RSTP

Answer:

Question 8 Selectable Answer

An engineer must design a routing solution for a company that is single-homed to an ISP. The company's goal is to run BGP between the CE and the PE devices. To support running BGP, the company obtained a public AS number and IP subnet from ARIN.
Which solution must the engineer select?

A. • The customer announces the public IP subnet to the ISP • The ISP announces the default route to the customer.
B. • The customer announces the public IP subnet to the ISP • The ISP announces the BGP table to the customer
C. • The ISP announces the customer public IP subnet. • The ISP announces the partial BGP table to the customer.
D. • The customer announces the default route to the ISP • The ISP announces the default route to the customer

Answer:

Question 9 Selectable Answer

A company uses cloud-based applications for voice and video calls, file sharing, content sharing, and messaging. During business hours, these applications randomly become slow and unresponsive. However, other applications work smoothly with the current applied QoS polices.
Which solution must the company choose to resolve the issue?

A. Identify the applications with NBAR2 and allocate the required bandwidth accordingly.
B. Identify the port used by each application and apply a minimum bandwidth guarantee.
C. Identify the applications and reserve the required bandwidth on the perimeter routers.
D. Identify the application ports, create groupings, and rate-limit the required bandwidth.

Answer:
Explanation:
using NBAR to identify application and bandwidth usage, then adjust existing QoS polices would be a more simple option. Of course, B is still ok if the network admin know all traffic and bandwidth consumption by other tools, say netflow.
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/qos_nbar/configuration/15-mt/qos-nbar-15-mt-book/nbar-protocl-discvry.html#GUID-ED1AEDA1-AE69-45C3-A77E-2AF881CA9C36
https://www.cisco.com/c/en/us/products/ios-nx-os-software/network-based-application-recognition-nbar/index.html

Question 10 Selectable Answer

Refer to the exhibit.

The failover time of ISP-2 is significantly shorter than ISP-1 when an interface on the ISP router toward the campus network fails.
Which solution minimizes the downtime to the sub-second?

A. Aggressive timers
B. Next-hop address tracking
C. Graceful-restart
D. BFD

Answer:
Explanation:
https://www.cisco.com/c/en/us/td/docs/ios/12_2sb/feature/guide/sbbnhop.html

Question 11 Selectable Answer

Refer to the exhibit.

A network engineer must improve the current IS-IS environment. The Catalyst switch is equipped with dual supervisors. Each time a stateful switchover occurs, the network experiences unnecessary route recomputation.
Which solution addresses this issue if the upstream router does not understand graceful restart messaging?

A. Enable IS-IS remote LFA FRR on both devices.
B. Enable NSR on the switch.
C. Enable NSF on the switch.
D. Configure ISIS aggressive timers on both devices.

Answer:

Question 12 Selectable Answer

Refer to the exhibit.

Which method must an architect use to provide connectivity between the mail servers?

A. ISATAP
B. 6to4
C. IPv4 compaliDie
D. 6rd

Answer:

Question 13 Selectable Answer

Which PIM mode uses a shared tree only?

A. bidirectional
B. sparse
C. dense
D. source-specific

Answer:
Explanation:
The PIM mode that uses a shared tree only is the sparse mode. In sparse mode, PIM routers build a shared tree for multicast traffic, which is shared among all of the routers in the multicast domain. The shared tree is built from the source routers to the rendezvous point (RP) and then from the RP to the receivers. The advantage of sparse mode is that it requires less state information on the routers.

Question 14 Selectable Answer

When vEdge router redundancy is designed, which FHRP is supported?

A. HSRP
B. OMP
C. GLBP
D. VRRP

Answer:

Question 15 Selectable Answer

Which consideration must be taken into account when using the DHCP relay feature in a Cisco SD-Access Architecture?

A. DHCP-relay must be enabled on fabric edge nodes to provide the correct mapping of DHCP scope to the local anycast gateway.
B. A DHCP server must be enabled on the border nodes to allow subnets to span multiple fabric edges.
C. DHCP servers must support Cisco SD-Access extensions to correctly assign IPs to endpoints in an SD-Access fabric with anycast gateway.
D. DHCP Option-82 must be enabled to map the circuit IP option to the access fabric node where the DHCP discover originated.

Answer:
Explanation:
https://www.cisco.com/c/en/us/td/docs/cloud-systems-management/network-automation-and-management/dna-center/tech_notes/sda_dhcp/b_cisco_sda_dhcp.html

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