Cisco 300-630 - Implementing Cisco Application Centric Infrastructure - Advanced (DCACIA)

 To allow communication between two application profiles that are configured in the same tenant but different VRFs, the contract scope must be set to ‘tenant.’ This is because the contract scope defines the level at which the contract is enforced. A ‘tenant’ scope means the contract applies to all application profiles within the same tenant, regardless of the VRFs they are in. This allows for the necessary route-leaking between the provider and consumer VRFs to enable communication between the application profiles.

 Migrating from Cisco NX-OS VXLAN to Cisco ACI fabric involves several considerations to minimize impact on workloads. Disabling bridge domain unicast routing while the default gateway remains in the VXLAN infrastructure ensures that the migration does not disrupt the existing traffic flow. This approach allows for a smoother transition by maintaining the current routing paths until the migration is complete123.

References := Implementing Cisco Application Centric Infrastructure Official Cert Guide

In the given scenario where CDP is disabled, LLDP is enabled, and LACP is in Active mode between Cisco UCS FIs and Cisco ACI leaf switches for the DVS setup, the compatible discovery protocol would be LLDP since it’s already enabled. As for load-balancing mechanisms with this setup: MAC Pinning can be used without relying on any link discovery protocol like CDP or LACP; hence option B is valid. Option F suggests usingLACP in Passivemode, whichcould complement the existing Active mode on other devicesto establishan LACP negotiation successfully. References: =Implementing Cisco Application Centric Infrastructure Official Cert Guide

The topology change notification (TCN) in Spanning Tree Protocol (STP) triggers a flush of the MAC address table. When a leaf node receives a TCN, it flushes the MAC address entries associated with the VLANs affected by the topology change. In this case, since the TCN is related to VLAN 101, the ACI fabric will flush all endpoints associated with VLAN 101 in bridge domain BD10123 on the leaf node.

The Forwarding Tag (FTAG) in Cisco ACI is used to load balance multi-destination traffic. FTAG trees facilitate efficient forwarding of multicast traffic within the fabric, ensuring optimal distribution and load balancing across multiple paths. All multi-destination traffic isencapsulated within VXLAN, and FTAG trees play a crucial role in achieving efficient traffic flow345.

References: Implementing Cisco Application Centric Infrastructure Official Cert Guide

 To limit both local and remote endpoint learning to instances where the source IP address belongs to a bridge-domain subnet in the VRF instance, the action that should be taken inside the Cisco APIC is to enable the “Enforce Subnet Check” feature. This configuration ensures that IP addresses outside the configured subnets for the bridge domain are not learned, preventing mis-learning of IP addresses that do not belong to the fabric12.

Configuring the Attachable Entity Profile (AEP) on a physical domain is necessary to ensure server ports can migrate to a different leaf switch in the event of a catastrophic failure. This configuration associates server ports with specific leaf switches and allows for seamless migration of connections without relying on Link Aggregation Control Protocol (LACP), which the server NICs do not support. References := ( Implementing Cisco Application Centric Infrastructure Official Cert Guide )

 In Cisco ACI, contracts are used to define the policies that govern communication between End Point Groups (EPGs). A contract specifies which types of traffic are permitted or denied between EPGs. To allow all IP traffic except SSH, you would configure the contract to permit all IP traffic and then deny SSH specifically. This is typically done by defining filters within the contract that match on the SSH protocol and setting the action to deny.

References:

Implementing Cisco Application Centric Infrastructure - Advanced (DCACIA) course materials and official certification guide can provide more detailed information on this topic12.

Cisco’s official documentation and training materials are also a good resource for understanding the configuration and management of contracts in ACI

When allowing routes learned from one L3Out to be advertised out another L3Out, the Export Route Control Subnet should be enabled, and Aggregate Export should also be enabled. This configuration allows the necessary routes within the specified CIDR block to be aggregated and advertised out, facilitating efficient route advertisement without the need for an explicit list of all routes.

References: Implementing Cisco Application Centric Infrastructure Official Cert Guide