Free Practice Questions for Cisco 300-620 Exam

In a Cisco ACI Multi-Pod architecture, multiple pods (each with its own leaf-and-spine topology) are interconnected via an Inter-Pod Network (IPN). The key characteristic of the Multi-Pod setup is that it is managed as a single fabric by a single APIC cluster, simplifying operations and maintaining consistency across all pods.

To meet the server team’s requirements for VMM integration with ESXi servers, the two enhanced LAG policies that should be configured are:

LB Mode: Destination IP Address and TCP/UDP Port (Option B): This load balancing mode ensures that traffic is evenly distributed across all available links based on the destination IP address and the TCP/UDP port numbers, which can provide a balanced traffic flow for different sessions.

LACP Mode: LACP Active (Option E): Setting the LACP mode to active allows the network switches to initiate the LACP negotiation, which is necessary when the servers are not configured to initiate the LACP process.

These settings ensure that the LAG group consisting of two 10 Gigabit Ethernet links will have traffic evenly distributed across them and that the network switches will initiate the LACP negotiation as required by the server team.

The scenario involves associating EPG-A with a Virtual Machine Manager (VMM) domain, setting the Deployment and Resolution preferences to Immediate, and attaching the host (generating endpoints for EPG-A) to Leaf-101 and Leaf-102 via eth1/1. However, no configuration for EPG-A is pushed to the leaf switches. This suggests an issue with the discovery or communication between the ACI fabric and the host. Let’s analyze the options based on Cisco ACI documentation.

Requirement Analysis

The VMM domain integration (e.g., VMware vCenter) relies on protocols like Cisco Discovery Protocol (CDP) or Link Layer Discovery Protocol (LLDP) to detect and map virtualized endpoints to the correct EPG.

The "Immediate" preference ensures that policies are applied as soon as endpoints are detected, but this requires proper protocol support for host discovery.

No configuration on the leaf switches indicates a failure in endpoint detection or policy application.

Option Evaluation

A. Enable CDP or LLDP on the host:

ACI uses CDP or LLDP to discover hosts and their interfaces when integrated with a VMM domain. If the host does not have CDP or LLDP enabled, the ACI fabric cannot detect the host’s attachment to Leaf-101 and Leaf-102, preventing EPG-A configuration from being pushed. Enabling these protocols on the host resolves the issue.

 In Cisco ACI, the object classes are used to categorize different types of managed objects within the ACI model. The output presented is indicative of a Tenant class object. Tenants in ACI are a top-level container for application policies, essentially providing a unit of isolation from other tenants. Each tenant can contain its own application policies, services, and network policies, and they are separate from other tenants to ensure multi-tenancy1.

References :=

Cisco ACI Policy Model Guide1

Object Renaming in Cisco ACI - Cisco2

Application Centric Infrastructure (ACI) REST API Guide - Cisco DevNet

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci /apic/sw/4-x/openstack/ACI-Installation-Guide-for-Red-Hat-Using-OSP13-Director/m-configuring-ironic-for-openstack.html

 In Cisco ACI, communication between Endpoint Groups (EPGs) is controlled by contracts. Contracts define the types of traffic and the rules that govern how EPGs can communicate with each other. They act as a policy framework that enforces security and segmentation within the ACI fabric.

In the Cisco ACI fabric, Spanning Tree Protocol (STP) Bridge Protocol Data Units (BPDUs) are flooded within the bridge domain VLAN. This allows the BPDUs to be propagated throughout the bridge domain, enabling STP to function correctly for the associated VLAN.

The question asks about the mechanism Cisco ACI uses to detect silent hosts when Layer 3 routed traffic is destined to the ACI fabric. A "silent host" refers to an endpoint that does not initiate traffic or send ARP requests, making detection challenging without specific mechanisms. Let’s evaluate the options based on Cisco ACI documentation and best practices.

Requirement Analysis

Layer 3 routed traffic implies that the ACI fabric is handling IP routing, and the detection mechanism must work within the context of the bridge domain and endpoint learning.

Silent hosts require passive detection methods since they do not generate active traffic (e.g., ARP requests).

The solution must align with ACI’s endpoint learning and proxy mechanisms.

Option Evaluation

A. Gratuitous ARP:

Gratuitous ARP (GARP) is a mechanism where a host announces its IP-to-MAC mapping to update network devices. However, this requires the host to send the GARP, which a silent host does not do. ACI can use GARP when hosts are active, but it is not the primary method for silent hosts.

The two protocols that support accessing backup files on a remote location from the APIC are FTP (File Transfer Protocol) and SFTP (SSH File Transfer Protocol). Both FTP and SFTP allow for the transfer of files to and from a remote location, but SFTP provides an additional layer of security by utilizing SSH.

The engineer configures port 1/2 on Leaf-101 and Leaf-102 to connect to a new server (SVR-12), which belongs to EPG-12 using VLAN-1212 encapsulation. The server is configured as a vPC member port and statically bound to EPG-12. The task is to ensure connectivity, indicating a missing configuration step.

Requirement Analysis

Static binding of a vPC member port to an EPG requires proper VLAN association and domain mapping.

vPC ensures redundancy, and the VLAN (1212) must be allocated and associated with the EPG via a domain (e.g., VMM or physical domain).

Option Evaluation

A. Create a VPC Explicit Protection Group for EPG-12 and VLAN-1212:

vPC Explicit Protection Groups are used for specific vPC configurations, but this is not a standard requirement for EPG binding and VLAN association.