300-610 Designing Cisco Data Center Infrastructure (DCID) Practice Questions

FCIP encapsulates large Fibre Channel frames into IP packets. To avoid fragmentation, which significantly degrades performance, the IP network path must support jumbo frames (MTU of 9000 or higher). Furthermore, since storage replication is highly sensitive to latency and packet loss, a robust Quality of Service (QoS) policy is essential to prioritize FCIP traffic and protect it from congestion caused by other applications sharing the WAN link.

Enabling fabric failover on the vNIC in the service profile is the primary mechanism. This tells the VIC adapter to treat the two fabric paths (to FI-A and FI-B) as an active/standby pair. If the primary path fails, the VIC hardware automatically redirects traffic to the secondary path.

This feature is dependent on the intelligence of the Cisco Virtual Interface Card (VIC). The VIC adapter presents a single NIC to the operating system but manages the two underlying physical paths. Without a VIC, hardware-level failover is not possible.

Cisco Intersight Cloud Orchestrator (ICO) is the service designed for creating and executing complex, automated workflows. It provides a drag-and-drop interface to chain together various tasks, such as applying server profiles (which contain BIOS, vNIC, and other policies) and triggering OS installations, into a single, cohesive workflow.

Graceful Restart (GR), along with Non-Stop Forwarding (NSF), allows a router undergoing a control plane failure or restart to signal its neighbors. These neighbors (GR-aware) will maintain their adjacency and continue forwarding traffic to the restarting router based on its pre-failure forwarding entries (FIB). This prevents a network-wide reconvergence event, maintaining data plane forwarding and significantly improving overall network stability.

Oversubscription is the ratio of the total bandwidth of host-facing ports to the total bandwidth of uplink (Inter-Switch Link) ports. A high ratio (e.g., 8:1) means many hosts are sharing a smaller amount of uplink bandwidth. During traffic bursts where many hosts simultaneously require high bandwidth, the uplinks can become congested, leading to backpressure, increased latency, and potentially dropped frames, which severely impacts application performance.

End-Host Mode (EHM) is the correct choice. In EHM, the Fabric Interconnects behave like a large network interface card (NIC) aggregator to the upstream network. They do not run STP on their uplinks and instead rely on pinning traffic to specific uplinks, which prevents loops. Switch Mode would make the FIs act as standard Ethernet switches, participate in STP, and would not meet the design requirement of isolating the UCS domain from the upstream STP.

Multipath I/O (MPIO) is a framework that allows storage traffic to be load-balanced across multiple physical paths between the initiator (ESXi host) and the target (storage array). This is achieved at the host level, using multiple VMkernel adapters for iSCSI, and does not require special switch configurations like port-channels. It provides both redundancy and performance scaling.

The nxos_config modules (and other resource-specific modules like nxos_vlans or nxos_vrfs) are designed for declarative, state-based management. By defining the state: present or state: absent parameters, the module ensures the device's configuration matches the desired state defined in the playbook, making the operation idempotent. The nxos_command module is imperative, simply running commands without knowledge of the current state, and is less suitable for this requirement.

The BGW acts as the gateway for inter-site traffic. It decapsulates VXLAN traffic from local VTEPs.

After decapsulation, the BGW re-originates the traffic into a new tunnel across the DCI network to the BGW in the destination site. This isolates the failure domains of each site.

This statement is false. Both vNIC templates (using MAC pools) and vHBA templates (using WWNN/WWPN pools) are designed to automate the assignment of unique hardware identifiers. This is a fundamental principle of stateless computing in Cisco UCS, allowing for rapid and consistent server provisioning.