Cisco CCNP 300-620 Questions & Answers

• Question 41:

  An engineer needs to avoid loops in the ACI network and needs an ACI leaf switch to error-disable an interface if the interface receives an ACI-generated packet. Which action meets these requirements?

  A. Set Rogue EP Control in the Endpoint Controls Policy.

  B. Uncheck the Loop Protection Action check box in MCP Instance Policy.

  C. Enable the Loop Indication by MCP event in the Error Disabled Recovery Policy.

  D. Change the default administrative state of the global MCP Instance Policy.

  Correct Answer: D

  MisCabling Protocol (MCP) detects loops from external sources (i.e., misbehaving servers, external networking equipment running STP, etc.) and will err-disable the interface on which ACI receives its own packet. Enabling this feature is a best practice, and it should be enabled globally and on all interfaces, regardless of the end device.

  For MCP to be enabled, you need to have it enabled globally and on a per-interface basis. While MCP is enabled on all interfaces by default, it is not turned “on” until you also enable it globally. The global configuration knob for MCP can be enabled by configuring the global settings here: Fabric > Access Policies > Global Policies > MCP Instance Policy default.

  https://www.cisco.com/c/dam/en/us/solutions/collateral/data-center-virtualization/application-centric-infrastructure/aci-guide-using-mcp-mis-cabling-protocol.pdf

• Question 42:

  Refer to the exhibit.

  

  A service provider hosts applications for multiple organizations. Each organization owns a separate tenant and syslog server. The events from each tenant must be sent to the corresponding syslog server. Which action accomplishes this goal?

  A. Configure a single shared external syslog server and apply it to all of the user tenants.

  B. Configure a single shared external syslog server and apply it to the common tenant.

  C. Configure an external syslog server for each tenant and apply each of them to the related tenant.

  D. Configure an external syslog server for each tenant and apply all of them to the common tenant.

  Correct Answer: C

• Question 43:

  Which two external entities are referenced by an AEP? (Choose two.)

  A. Layer 3 domain

  B. Hypervisor

  C. VMM domain

  D. Fibre Channel switch

  E. VMware vCenter server

  Correct Answer: AC

• Question 44:

  Refer to the exhibit.

  

  All nodes in the Cisco ACI fabric have been statically assigned out-of-band management IP addresses in the 10.100.180.0/24 range. An engineer is attempting to SSH into Leaf101 using a laptop with an IP address of 10.101.180.100/24. Which configuration change must be performed to allow the engineer to SSH using the laptop?

  A. Add a contract filter to oobbrc-default that allows SSH.

  B. Change the Leaf101 IP address to 10.101.180.101.

  C. Change the allowed subnets.

  D. Select the default QoS Class policy.

  Correct Answer: C

• Question 45:

  A recent set of changes by a Cisco ACI administrator corrupted the APIC cluster. The ACI engineer must restore the configuration of the previous day. The APIC nodes in the cluster can communicate but fail to connect with other networks. The administrator plans to overwrite the entire existing configuration with the backup configuration. Which set of actions accomplishes this task?

  A. Restore using the last configuration on the factory-reset APIC. Use an import policy set to Best-effort.

  B. Roll back the configuration using a local snapshot. Use an import policy set to Atomic Replace.

  C. Roll back the configuration using a local snapshot. Use an import policy set to Best-effort Merge.

  D. Restore the configuration imported from an FTP server. Use an import policy set to Atomic.

  Correct Answer: B

  Atomic Replace - overwrites existing configuration with imported configuration data. Any objects in the existing configuration that do not exist in the imported configuration are deleted. Objects are deleted from the existing configuration that have children in the existing configuration but do not have children in the incoming imported configuration. For example, if an existing configuration has two tenants, solar and wind, but the imported backed up configuration was saved before the tenant wind was created, tenant soar is restored from the backup but tenant wind is deleted.

  Rollback is when a previous configuration snapshot is used to replace the current APIC configuration. This can be done on the granularity of a snapshot file. This means that a single tenant can be moved back to a previous configuration while the other tenants keep their current configuration state. This is often referred to as partial rollback. When all of the configuration files for a particular version are used to replace the current APIC configuration, this is referred to as a full rollback.

• Question 46:

  Which protocol is used in a Multi-Pod topology to synchronize reachability information across pods?

  A. MP-BGP EVPN

  B. OSPF

  C. IS-IS

  D. COOP

  Correct Answer: A

  Each Pod connects to the IPN through the spine nodes, the IPN can be as simple as a single Layer 3 device or can be built with a larger Layer 3 network infrastructure like a Service Provider network.

  Since each Pod is running a separate instance of the COOP protocol, this implies that information about discovered endpoints (MAC, IPv4/IPv6 addresses, and their location) is only exchanged using COOP as a control plane protocol between the leaf and spine nodes locally deployed in each Pod.

  ACI Multi-Pod functions as a single fabric, so, it is key to ensure that the databases implemented in the spine nodes across Pods have a consistent view of the endpoints connected to the fabric, this requires the deployment of an overlay control plane running between the spines and used to exchange endpoint reachability information. Multi-Protocol BGP has been chosen for this function. This is due to the flexibility and scalability properties of this protocol and its support of different address families (like EVPN and VPNv4) allowing the exchange of Layer 2 and Layer 3 information in a true multi-tenant fashion.

• Question 47:

  Refer to the exhibit.

  

  A load balancer is connected to the Cisco ACI fabric using a single interface. The load balancer is performing source and destination NAT. A service graph is configured on the Cisco ACI. Which action must be taken to allow traffic from host A to pass through the load balancer before reaching host B?

  A. Apply PBR on contract between the load balancer and application EPGs.

  B. Disable unicast routing on the bridge domain BD_2.

  C. Configure limit IP learning to subnet on BD_3.

  D. Set the default gateway for host B on the load balancer.

  Correct Answer: A

  https://www.cisco.com/c/en/us/solutions/collateral/data-center-virtualization/application-centric-infrastructure/white-paper-c11-739971.html

• Question 48:

  Refer to the exhibit.

  

  A Cisco ACI fabric has these configurations:

  1.

  VPC exists between Leaf2 and Leaf3.

  2.

  A switch profile called SW_Prof exists.

  3.

  A switch selector called SW_Selec exists.

  4.

  An interface selector named Int_Selec exists.

  5.

  An interface profile named Int_Prof exists.

  Which two sets of actions must the engineer perform to connect Server1 to Leaf2 and Leaf3 using VPC? (Choose two.)

  A. Map switch selector SW_Selec under switch profile SW_Prof. Add Leaf2 and Leaf3 node IDs under switch selector SW_Selec. Assign policy group to interface selector Int_Selec.

  B. Add Leaf2 and Leaf3 node IDs under switch selector SW_Selec. Map switch profile SW_Prof under switch selector SW_Selec. Create the explicit VPC group from access policies.

  C. Create the explicit VPC group from fabric policies. Map interface Eth1/1 under interface selector Int_Selec. Assign policy group to interface selector Int_Selec.

  D. Add Leaf2 and Leaf3 node IDs under switch profile SW_Prof. Map Int_Selec under Int_Prof. Assign policy group to interface profile Int_Prof.

  E. Create the explicit VPC group from access policies. Map Interface Eth1/1 under interface selector Int_Selec. Map Int_Selec under Int_Prof.

  Correct Answer: AE

• Question 49:

  Refer to the exhibit.

  

  An engineer plans to upgrade the Cisco ACI fabric. Leaf1 and Leaf2 are deployed in a VPC. The fabric is peering with R1 using BGP protocol.

  Which two actions upgrade the fabric nondisruptively? (Choose two.)

  A. Configure the Graceful upgrade option.

  B. Disable the BGP neighborship between Cisco ACI fabric and R1.

  C. Enable the Graceful Insertion and Removal option.

  D. Configure one maintenance group for every leaf.

  E. Create one update group for all spines.

  Correct Answer: AC

• Question 50:

  A customer is deploying a new application across two ACI pods that is sensitive to latency and jitter. The application sets the DSCP values of packets to AF31 and CS6, respectively. Which configuration changes must be made on the APIC to support the new application and prevent packets from being delayed or dropped between pods?

  A. disable DSCP mapping on the IPN devices

  B. disable DSCP translation policy

  C. align the ACI QoS levels and IPN QoS policies

  D. align the custom QoS policy on the EPG site in the customer tenant

  Correct Answer: C

  In order to preserve the proper QoS Level of the packet and avoid high priority packets from being delayed or dropped, you can use a DSCP translation policy for traffic that goes between multiple PODs connected by an IPN.

  Also Note For traffic passing through the IPN, do not map any DSCP values to CS6. Which leaves only C as viable answer. As you have to align QoS. as per ref:https://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/kb/Cisco-APIC-and-QoS.html#id_34903