Question 1

In which situation do you need to select switches with a back-front (BF) airflow?

Accepted Answer

D

Explanation: In a standard Top-of-Rack (ToR) data center deployment, switches are installed in the same rack as the servers they connect. For efficient cabling and management, the switch ports are aligned to face the same direction as the server network ports, which is typically the rear of the rack in the hot aisle. To maintain the data center's hot-aisle/cold-aisle cooling design, the switch must draw cool air from the cold aisle (at the back of the switch) and exhaust hot air into the hot aisle (from the port-side/front of the switch). This cooling scheme is known as back-to-front (BF) or port-side exhaust airflow.

Question 2

You are adding EVPN VXLAN to an L3 spine and leaf topology that uses OSPF for the underlay. You plan to use a single BGP AS. Which design for EVPN neighbors is correct?

Accepted Answer

C

Explanation: In a spine-and-leaf fabric using a single BGP AS for the EVPN control plane, the standard and most scalable design utilizes route reflectors (RRs) to avoid a full mesh of iBGP sessions between all leaf switches (VTEPs). The spine switches are the ideal location for the RR function due to their central position in the topology, connecting to all leaf switches. Leaf switches are configured as RR clients and establish iBGP sessions with the spine RRs. These sessions must be established between loopback interfaces to ensure control plane stability, as loopback interfaces remain active even if a specific physical link fails. The underlay protocol (OSPF) provides the necessary reachability between these loopback interfaces.

Question 3

Which of these is a key CX EVPN VXLAN capability?

Accepted Answer

C

Explanation: A key capability of EVPN VXLAN on Aruba CX switches is ARP suppression. The BGP EVPN control plane distributes host MAC and IP address information (MAC-IP bindings) among all VTEPs in the fabric. When a VTEP receives an ARP request from a local host, it can intercept the request and, if it has the binding information for the target IP, reply on behalf of the remote host. This prevents the ARP request (a broadcast) from being flooded across the entire VXLAN overlay network. This significantly reduces BUM (Broadcast, Unknown Unicast, and Multicast) traffic, leading to a more efficient and scalable network.

Question 4

Which of these protocols carries commands for reading from/writing to storage over a TCP/IP session?

Accepted Answer

B

Explanation: iSCSI (Internet Small Computer System Interface) is a storage networking protocol designed to transport SCSI commands over TCP/IP networks. It operates at the session layer of the OSI model, encapsulating SCSI commands and data into TCP packets for transmission across standard Ethernet infrastructure. This allows for the creation of IP-based Storage Area Networks (SANs) using existing network hardware. The protocol establishes a reliable, connection-oriented session via TCP (typically on port 3260) to facilitate block-level read and write operations between an initiator (client) and a target (storage server).

Question 5

Which technology uses LLDP TLVs to tell connected devices information such as the correct queue for PFC?

Accepted Answer

D

Explanation: Data Center Bridging Capability Exchange (DCBx) is the correct technology. It is an extension of the Link Layer Discovery Protocol (LLDP) that uses specific Type-Length-Value (TLV) fields to communicate and negotiate Data Center Bridging (DCB) parameters between network switches and adapters. This exchange ensures that both ends of a link have a consistent configuration for features like Priority-based Flow Control (PFC), including which traffic classes (queues) are designated as no-drop, and Enhanced Transmission Selection (ETS) for bandwidth management.

Question 6

In preparation for the deployment, what statement is correct from the below?

Accepted Answer

D

Explanation: The most reliable and least disruptive method for network migration is a phased approach. This involves migrating Layer 2 functionality first to establish and validate basic network connectivity and VLAN trunking between the existing and new infrastructure. Once Layer 2 is confirmed to be stable and operating as expected, the Layer 3 functions, such as the default gateways (e.g., Switched Virtual Interfaces - SVIs), are migrated. This sequential process isolates potential faults to a specific layer, significantly simplifying troubleshooting and reducing the overall risk and impact of the cutover.

Question 7

Two VMs on the same ESXi host are assigned to an isolated VLAN 2001 (primary VLAN 1001). The
host connects to an HPE Aruba CX 10000 switch on an access port. The switch supports the same
PVLAN settings. VM 1 sends traffic to VM 2. Which policy or policies does the switch apply (assuming
that they exist)?

Accepted Answer

A

Explanation: The HPE Aruba CX 10000 is a Distributed Services Switch that utilizes a Data Processing Unit (DPU) to extend policy enforcement to workloads within the server. Even though the two VMs are on the same ESXi host, the DPU intercepts the traffic between them. Private VLAN (PVLAN) rules dictate forwarding behavior. An isolated VLAN prevents communication between any two member ports. When VM1 sends traffic to VM2, the DPU receives the traffic (ingress) and performs a forwarding lookup. The PVLAN policy, which is associated with the primary VLAN (1001), prevents the traffic from being forwarded to another isolated port. This action of controlling where traffic can be sent is an egress function. Therefore, the switch applies an egress policy on the primary VLAN 1001 to block the traffic.

Question 8

A customer currently has a three-tier architecture in which aggregation switches are the default
gateways. Pairs of aggregation switches use VRRP. You are migrating to an L2 two-tier architecture in
which the core switches are the default gateways. How should you migrate the default gateway
functionality?

Accepted Answer

B

Explanation: The most effective and modern method for this migration is to leverage Virtual Switching Extension (VSX) Active Gateway on the new core switches. To ensure a seamless transition with minimal disruption to end devices (servers), it is critical to reuse the existing default gateway IP address. By configuring the VSX Active Gateway with the same virtual IP address previously used by VRRP, servers do not need to be reconfigured. This approach migrates the gateway functionality directly to the intended, modern, active-active architecture. While reusing the existing VRRP MAC address is also a best practice for a truly hitless migration, reusing the IP address is the most critical element presented in the correct option.

Question 9

If you need to demo the proposed solution you should only use certified Aruba demo portal only

Accepted Answer

[FALSE]

Explanation: The statement is incorrect because it presents an absolute condition that is not reflective of standard industry practice or Aruba's own methodologies. While the certified Aruba demo portal is a valuable, sanctioned, and often recommended tool for showcasing solutions in a controlled environment, it is not the only method that should be used. Other critical and frequently employed methods for demonstrating a proposed solution include: On-premises Proof of Concept (PoC): Deploying physical or virtual Aruba hardware and software in the customer's own environment to validate the design, test performance, and demonstrate integration with their existing infrastructure. This is often essential for complex or large-scale opportunities. Partner or In-House Lab Demonstrations: Utilizing dedicated lab environments built with actual Aruba equipment to create customized demonstrations that mirror a customer's specific requirements more closely than a generic portal demo might allow. The choice of demonstration method is dictated by the customer's needs, the complexity of the proposed solution, and the objectives of the validation phase. Restricting demonstrations solely to a certified portal would preclude these other vital validation techniques.

Question 10

When Data Centers are in the same campus, a simple solution could be a VSX LAG between pairs of VSX switches that allows the extension of L2 domains:

Accepted Answer

TRUE

Explanation: The statement accurately describes a common and valid Data Center Interconnect (DCI) architecture for campus environments using Aruba VSX technology. A VSX Link Aggregation Group (LAG) can be established between two distinct VSX pairs, with one pair in each data center. This configuration creates a resilient, high-bandwidth, loop-free Layer 2 path between the data centers. This path functions as a trunk, enabling the seamless extension of VLANs and their corresponding broadcast domains across the two physical sites, which is a primary goal of L2 DCI.

Question 11

Aruba CX 6200 are the only switches that support VSF and VSX stacking

Accepted Answer

[FALSE]

Explanation: The statement is false for two primary reasons. First, the Aruba CX 6200 Switch Series supports VSF (Virtual Switching Framework) stacking, but it does not support VSX (Virtual Switching Extension). VSX is a high-availability virtualization technology designed for core and aggregation switches, such as the Aruba CX 6400, 8xxx, and 10000 series, to provide redundancy and load balancing without traditional stacking. The CX 6200 is an access layer switch and is not equipped with this feature. Second, the Aruba CX 6200 is not the only switch series that supports VSF. The Aruba CX 6300 Switch Series also supports VSF stacking. Therefore, the claim that the CX 6200 is the "only" switch with these capabilities is incorrect. Why the "True" Option is Wrong: Selecting "True" would incorrectly assert that the Aruba CX 6200 switch supports VSX technology, which it does not. It would also incorrectly claim exclusivity for VSF support to the CX 6200 series, which is also false as other series like the CX 6300 support it.

Question 12

Which CX switch model supports ERPS/VSX DCI?

Accepted Answer

C

Explanation: The Aruba 8325 Switch Series is a high-performance data center and core switch platform running the ArubaOS-CX network operating system. It is specifically designed to support advanced resiliency and Data Center Interconnect (DCI) features. The combination of Virtual Switching Extension (VSX) for device-level redundancy and Ethernet Ring Protection Switching (ERPS) for Layer 2 loop prevention is a validated DCI solution on the 8325 platform. This architecture provides a highly available, loop-free, and resilient network fabric suitable for interconnecting data centers.

Question 13

Choose the most suitable technology for the DCI (Data Center Interconnect) when Data Centers are geographically not in the same building:

Accepted Answer

B

Explanation: Ethernet Ring Protection Switching (ERPS), defined by the ITU-T G.8032 standard, is specifically designed for resilient ring topologies commonly found in Metropolitan Area Networks (MAN) or carrier networks. This makes it highly suitable for interconnecting geographically separate data centers. ERPS provides rapid convergence times (sub-50ms), ensuring high availability for the Layer 2 DCI link. When combined with the Virtual Router Redundancy Protocol (VRRP), it creates a complete solution that offers both a resilient Layer 2 path and a redundant Layer 3 default gateway for workloads across the data centers.

Question 14

You need to design a network that supports transmitting RDMA traffic over multiple IP hops. Which protocols must the switches support? (Select all that apply.)

Accepted Answer

A, B, C

Explanation: Designing a network for multi-hop (routed) RDMA over Converged Ethernet (RoCEv2) requires a fabric that is both lossless and capable of managing congestion end-to-end. Priority-based Flow Control (PFC) is essential to prevent packet loss from buffer overruns on a hop-by-hop basis, creating the necessary lossless behavior for RoCE. Enhanced Transmission Selection (ETS) allocates a guaranteed minimum bandwidth to the RoCE traffic class, ensuring it is not starved by other traffic types. IP Explicit Congestion Notification (ECN) is the standard Layer 3 mechanism used in RoCEv2 deployments to signal network congestion from switches to endpoints without dropping packets, allowing the sender to adjust its rate and prevent congestion collapse across multiple hops.

Question 15

In L3 spine and leaf design

Accepted Answer

C

Explanation: In a Layer 3 (L3) spine and leaf architecture, the connections between the spine and leaf switches are configured as routed (L3) interfaces. Routing protocols like BGP or OSPF are used to exchange reachability information. This design inherently prevents Layer 2 loops between the spine and leaf tiers, as frames are not flooded in the same way as in a traditional L2 network. Each router hop decrements the IP packet's Time-to-Live (TTL) field, which prevents indefinite packet forwarding loops. Consequently, Layer 2 loop prevention mechanisms like Spanning Tree Protocol (STP) are not required for the fabric's core infrastructure, allowing all inter-switch links to be active and forward traffic simultaneously using Equal-Cost Multi-Path (ECMP).

Free HP HPE7-A04 Actual Exam Questions