Cisco 642-997 Online Practice Questions and Exam Preparation

Cisco 642-997 Online Questions & Answers

• Question 61:

  Refer to the exhibit.

  

  What is the consequence of configuring peer-gateway on the two vPC peers N7K-1 and N7K-2?

  A. Nothing, this is the standard vPC configuration to make the feature work.
  B. The downstream device detects only one of the vPC peers as its gateway.
  C. The downstream device can use DMAC of N7K-1 on the link to N7K-2, and N7K-2 forwards the packet.
  D. This configuration enables the downstream device to use DHCP to obtain its default gateway.
  C. The downstream device can use DMAC of N7K-1 on the link to N7K-2, and N7K-2 forwards the packet.

  ---

  Beginning with Cisco NX-OS 4.2(1), you can configure vPC peer devices to act as the gateway even for packets that are destined to the vPC peer device's MAC address. Use the peer-gateway command to configure this feature. Some network-attached storage (NAS) devices or load-balancers may have features aimed to optimize the performances of particular applications. Essentially these features avoid performing a routing-table lookup when responding to a request that originated form a host not locally attached to the same subnet. Such devices may reply to traffic using the MAC address of the sender Cisco Nexus 7000 device rather than the common HSRP gateway. Such behavior is non-complaint with some basic Ethernet RFC standards. Packets reaching a vPC device for the non-local router MAC address are sent across the peer-link and could be dropped by the built in vPC loop avoidance mechanism if the final destination is behind another vPC. The vPC peer-gateway capability allows a vPC switch to act as the active gateway for packets that are addressed to the router MAC address of the vPC peer. This feature enables local forwarding of such packets without the need to cross the vPC peer-link. In this scenario, the feature optimizes use of the peer-link and avoids potential traffic loss. Configuring the peer-gateway feature needs to be done on both primary and secondary vPC peers and is non-disruptive to the operations of the device or to the vPC traffic. The vPC peer-gateway feature can be configured globally under the vPC domain submode. When enabling this feature it is also required to disable IP redirects on all interface VLANs mapped over a vPC VLAN to avoid generation of IP redirect messages for packets switched through the peer gateway router. When the feature is enabled in the vPC domain, the user is notified of such a requirement through an appropriate message. Packets arriving at the peer-gateway vPC device will have their TTL decremented, so packets carrying TTL = 1 may be dropped in transit due to TTL expire. This needs to be taken into account when the peer-gateway feature is enabled and particular network protocols sourcing packets with TTL = 1 operate on a vPC VLAN.

  Reference: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/4_2/nx- os/interfaces/configuration/guide/if_nxos/if_vPC.html

• Question 62:

  Which statement about core-edge SAN topology is true?

  A. Converged FCoE links connect the core and edge MDS switches.
  B. The SAN core connects to the network aggregation layer.
  C. Separate links with the same I/O are used for SAN and LAN traffic.
  D. Storage devices are accessed via FCoE over the LAN network.
  B. The SAN core connects to the network aggregation layer.

  ---

  The Aggregation layer of the data center provides connectivity for the Access layer switches in the server farm, an aggregates them into a smaller number of interfaces to be connected into the Core layer. In most data center environments, the Aggregation layer is the transition point between the purely Layer 3 routed Core layer, and the Layer 2-switched Access layer. 802.1Q trunks extend the server farm VLANs between Access and Aggregation layers. The Aggregation layer also provides a common connection point to insert services into the data flows between clients and servers, or between tiers of servers in a multi-tier application.

• Question 63:

  Which two items are required components of VN-Link in software? (Choose two.)

  A. VDC
  B. VEM
  C. vPC
  D. VSM
  E. VRRP
  B. VEM
  D. VSM

  ---

  The Cisco Nexus 1000V Series consists of two main types of components that can virtually emulate a 66-slot modular Ethernet switch with redundant supervisor functions:

  ?Virtual Ethernet module (VEM)-data plane: This lightweight software component runs inside the hypervisor. It enables advanced networking and security features, performs switching between directly attached virtual machines, provides

  uplink capabilities to the rest of the network, and effectively replaces the vSwitch. Each hypervisor is embedded with one VEM.

  ?Virtual supervisor module (VSM)-control plane: This standalone, external, physical or virtual appliance is responsible for the configuration, management, monitoring, and diagnostics of the overall Cisco Nexus 1000V Series system (that is,

  the combination of the VSM itself and all the VEMs it controls) as well as the integration with VMware vCenter. A single VSM can manage up to 64 VEMs. VSMs can be deployed in an active-standby model, helping ensure high availability.

  Reference: http://www.cisco.com/c/en/us/solutions/collateral/switches/nexus-1000v-switch- vmware-vsphere/white_paper_c11-525307.html

• Question 64:

  Refer to the exhibit.

  

  Which statement based on these two outputs that were collected 24 hours apart is true?

  A. The Site 2 OTV edge device has gone down.
  B. The MAC address cannot be discovered on two separate port channel interfaces.
  C. The MAC address that ends in 020a moved to the local site 23 hours ago.
  D. The Overlay1 IP address should be a multicast IP address.
  C. The MAC address that ends in 020a moved to the local site 23 hours ago.

• Question 65:

  Which three VDC resources can be constrained with a resource template? (Choose three.)

  A. ACLs
  B. NAT entries
  C. IPv4 routes
  D. IPv6 routes
  E. SPAN sessions
  F. RBAC users
  C. IPv4 routes
  D. IPv6 routes
  E. SPAN sessions

  ---

  VDC resource templates set the minimum and maximum limits for shared physical device resources when you create the VDC. The Cisco NX-OS software reserves the minimum limit for the resource to the VDC. Any resources allocated to the VDC beyond the minimum are based on the maximum limit and availability on the device. You can explicitly specify a VDC resource template, or you can use the default VDC template provided by the Cisco NX-OS software. VDC templates set limits on the following resources: IPv4 multicast route memory IPv6 multicast route memory IPv4 unicast route memory IPv6 unicast route memory Port channels Switch Port Analyzer (SPAN) sessions VLANs Virtual routing and forwarding instances (VRFs)

  Reference: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/nx- os/virtual_device_context/configuration/guide/b-7k-Cisco-Nexus-7000-Series-NX-OS- Virtual-Device-Context-Configuration-Guide/vdc-res-template.html

• Question 66:

  Which command sequence correctly enables Adapter FEX on Nexus 5000 Series Switches?

  A. switch(config)# install feature-set virtualization switch(config)# feature-set virtualization
  B. switch(config)# install feature-set adapter-fex switch(config)# feature-set adapter-fex
  C. switch(config)# install feature-set adapter-fex switch(config)# feature-set virtualization
  D. switch(config)# install feature-set virtualization switch(config)# feature-set adapter-fex
  A. switch(config)# install feature-set virtualization switch(config)# feature-set virtualization

  ---

  

  

  install feature-set virtualization : installs the cisco virtual machine feature set on the switch. feature-set virtualization : enables the cisco virtual machine feature on the switch.

  Reference: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/adapter- fex/513_n1_1/b_Configuring_Cisco_Nexus_5000_Series_Adapter- FEX_rel_5_1_3_N1/b_Configuring_Cisco_Nexus_5000_Series_AdapterFEX_rel_5_1_3_N1_chapter_010.pdf

• Question 67:

  Which parameter is configurable when setting up logging on the Connectivity Management Processor?

  A. the number of CMP messages to save in a single log file
  B. the number of times the log can roll over
  C. the directory to save the log file to
  D. the severity threshold of the messages to log
  D. the severity threshold of the messages to log

• Question 68:

  Which policy-map action performs congestion avoidance?

  A. priority
  B. bandwidth
  C. queue-limit D. random-detect
  D

  ---

  Congestion avoidance techniques monitor network traffic loads in an effort to anticipate and avoid congestion at common network bottlenecks. Congestion avoidance is achieved through packet dropping. Among the more commonly used congestion avoidance mechanisms is Random Early Detection (RED), which is optimum for high-speed transit networks. Cisco IOS QoS includes an implementation of RED that, when configured, controls when the router drops packets. If you do not configure Weighted Random Early Detection (WRED), the router uses the cruder default packet drop mechanism called tail drop.

  Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configuration/guide/fqos_c/qcfconav.ht ml

• Question 69:

  Which task must be done before a zone set takes effect?

  A. Add a member to the zone.
  B. Enter the exit config t command.
  C. Enter the copy running-config startup-config command.
  D. Enter the zoneset activate name vsan command.
  D. Enter the zoneset activate name vsan command.

• Question 70:

  Which example creates an Embedded Event Manager policy allowing the CLI command to execute, and triggers an SNMP notification when a user enters configuration mode?

  

  A. Option A
  B. Option B
  C. Option C
  D. Option D
  A. Option A