HPE7-A01 Questions and Answers

These are two correct statements regarding OSPFv2 route redistribution for Aruba OS CX switches. Route redistribution is a process that allows routes from one routing protocol or source to be injected into another routing protocol or destination. OSPFv2 is a link-state routing protocol that supports route redistribution from various sources, such as connected, static, BGP, etc. The “redistribute connected” command will redistribute all connected routes for the switch, including local loopback addresses, into OSPFv2. The “redistribute static route-map connected-routes” command will redistribute all static routes that have a matching permit statement in the route map named “connected-routes” into OSPFv2. The other statements are incorrect because they either do not reflect the correct behavior of route redistribution commands or do not exist as valid commands. References: https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch02.html https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch03.html

MPSK Local is a feature that can be used to set up 15 headless IoT devices that do not support 802.1X authentication. MPSK Local allows the switch to automatically generate and assign unique pre-shared keys for devices based on their MAC addresses, without requiring any configuration on the devices or an external authentication server. The other options are incorrect because they either require 802.1X authentication, which is not supported by the IoT devices, or WPA3 encryption, which is not supported by Aruba CX switches. References: https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch05.html https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch06.html

The show arp command displays the ARP table for a specific VRF or all VRFs on the switch. The ARP table contains the IP address to MAC address mappings for hosts that are directly connected to the switch or reachable through a gateway. If the client device is connected to another switch by VSX LAG, the ARP entry for the client device will not be present on the primary switch unless it has communicated with it recently. Therefore, to find the IP address of the client device, the administrator should run the show arp command on the secondary switch in the VSX pair, specifying the VRF name that contains the client device’s subnet. References: https://techhub.hpe.com/eginfolib/Aruba/OS-CX_10.04/5200-6692/GUID-9B8F6E8F-9C7A-4F0D-AE7B-9D8E6C5B6A7F.html

 The system-mac command is used to configure a fixed MAC address for the VSX system. This MAC address is used as the source MAC address for all routed traffic from the VSX node.  The system-mac command is highly recommended for preventing traffic disruptions when the primary VSX switch restores after the secondary VSX switch, such as during a primary switch hardware replacement or a power outage 2 . During the initial VSX configuration, the system-mac is assigned with a fixed MAC based on VSX ID.  The system-mac command can be used to change this default MAC address if needed 2 . Therefore, answer D is correct.

These are the correct statements about access from the servers to the Core when the ISL link between the switches fails, but the keepalive interface functions. Server 1 can access the core layer via both uplinks because it is connected to VSX-A, which is still active for VLAN 10. Server 2 can also access the core layer via its uplink to VSX-B, which is still active for VLAN 10 because of Active Gateway feature. Server 1 and Server 2 can communicate with each other via the core layer because they are in the same VLAN and subnet, and their traffic can be routed through the core switches. The other statements are incorrect because they either describe scenarios that are not possible or not relevant to the question. References: https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-

These are the correct requirements to ensure that WMM (Wi-Fi Multimedia) is working effectively. WMM is a standard that provides quality of service (QoS) for wireless networks by prioritizing traffic into four categories: voice, video, best effort, and background. To use WMM, both the APs and the controller must be Wi-Fi CERTIFIED for WMM, which means they have passed interoperability tests and comply with the standard. WMM must also be enabled on the APs and the controller, which is usually the default setting. The client device must also be Wi-Fi CERTIFIED for WMM and configured for WMM marking, which means it can tag its traffic with the appropriate priority level based on the application type. The other options are incorrect because they are either not related to WMM or not required for WMM to work. References: https://www.arubanetworks.com/techdocs/ArubaOS_86_Web_Help/Content/arubaos-solutions/wlan-qos/wmm.htm https://www.wi-fi.org/discover-wi-fi/wi-fi-certified-wmm

MPSK Local is a feature that can reduce the IT administration overhead associated with deploying devices that do not support 802.1X authentication while maintaining a secure environment. MPSK Local allows the switch to automatically generate and assign unique pre-shared keys for devices based on their MAC addresses, without requiring any configuration on the devices or an external authentication server. The other options are incorrect because they either require manual intervention by the installers or the MPSK gateway, or they do not provide unique pre-shared keys for devices. References: https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch05.html https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch06.html

The default value for config-revision on Core-1 is 0. Config-revision is a parameter that indicates the configuration version of a VSX pair. It is used to synchronize the configuration between the VSX peers and to detect any configuration mismatch. The config-revision value is set to 0 by default on both VSX peers and is incremented by 1 every time a configuration change is made on either peer. The other options are incorrect because they do not reflect the default value of config-revision. References: https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch07.html https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/bk01-ch02.html

To configure an IP address for an interface in default state for interface 1/1/1 on Aruba CX 6300 switch, you need to disable switching on the interface first with the command  no switching . Then you can assign an IP address with the command  ip address . The other options are incorrect because they either do not disable switching or use invalid keywords such as  switching  or  routing . References: https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch01.html https://www.arubanetworks.com/techdocs/AOS-CX_10_08/UG/bk01-ch02.html

The calculated Equivalent Isotropic Radiated Power (EIRP) for AP1 is 17 dBm.

EIRP is the measured radiated power of an antenna in a specific direction. It is equal to the input power to the antenna multiplied by the gain of the antenna. It can also take into account the losses in transmission line, connectors, and other components. The formula for EIRP is:

EIRP = P + G - L

where P is the output power of the radio, G is the gain of the antenna, and L is the loss of the cable and connectors.

For AP1, we have:

P = 10 dBm G = 9 dBi L = 2 dB

Therefore,

EIRP = 10 + 9 - 2 EIRP = 17 dBm

OSPF (Open Shortest Path First) is a routing protocol that uses link-state information to calculate the best path to each destination in the network.  OSPF establishes adjacencies with neighboring routers to exchange routing information and maintain a consistent view of the network topology 1 .

To establish an OSPF adjacency, the routers need to have some common parameters, such as the area ID, the network type, the hello interval, the dead interval, and the authentication method 2 .  The routers also need to have a matching subnet mask on the interface that connects them 3 .

In this case, the Aruba CX 6300 VSF stack has an SVI (Switched Virtual Interface) on VLAN 10 with an IP address of 10.1.1.1/24 and a LAG (Link Aggregation Group) on port 1/1/1 and port 2/1/1 that connects to a neighboring device. The SVI is configured with OSPF area 0 and network type broadcast. The LAG is configured with OSPF passive mode, which means that it will not send or receive OSPF hello packets.

The neighboring device has an interface with an IP address of 10.1.1.2/24 and a LAG on port 1/0/1 and port 2/0/1 that connects to the Aruba CX 6300 VSF stack. The interface is configured with OSPF area 0 and network type broadcast.

Since the Aruba CX 6300 VSF stack and the neighboring device have the same area ID, network type, subnet mask, and default hello and dead intervals on their interfaces, they will be able to establish an OSPF adjacency over SVI 10 with LAG 1. The OSPF passive mode on the LAG will not affect the adjacency, because it only applies to the LAG interface, not the SVI interface.

Splitting a larger OSPF area into a number of smaller areas has several advantages for network scalability and performance. Some of these advantages are:

It increases stability by limiting the impact of topology changes within an area. When a link or router fails in an area, only routers within that area need to run the SPF algorithm and update their routing tables. Routers in other areas are not affected by the change and do not need to recalculate their routes.

It reduces processing overhead by reducing the size and frequency of link-state advertisements (LSAs). LSAs are packets that contain information about the network topology and are flooded within an area. By dividing a network into smaller areas, each area has fewer LSAs to generate, store, and process, which saves CPU and memory resources on routers.

It reduces bandwidth consumption by reducing the amount of routing information exchanged between areas. Routers that connect different areas, called area border routers (ABRs), summarize the routing information from one area into a single LSA and advertise it to another area. This reduces the number of LSAs that need to be transmitted across area boundaries and saves network bandwidth.

802.11k is a standard that provides mechanisms for APs and clients to dynamically measure the available radio resources in a wireless network. 802.11k defines radio resource management (RRM) functions, such as neighbor reports, link measurement, beacon reports, etc., that allow APs and clients to exchange information about the RF environment and make better roaming decisions. The other options are incorrect because they describe other standards, such as 802.11r, 802.11v, or 802.11ax. References: https://www.arubanetworks.com/assets/wp/WP_WiFi6.pdf https://www.arubanetworks.com/assets/ds/DS_AP510Series.pdf

The Equivalent Isotropic Radiated Power (EIRP) is the measured radiated power of an antenna in a specific direction. It is also called Equivalent Isotropic Radiated Power. It is the output power when a signal is concentrated into a smaller area by the Antenna. The EIRP can take into account the losses in transmission line, connectors and includes the gain of the antenna. It is represented in dB 2 . The formula for EIRP is:

EIRP = PT − Lc + Ga

where PT is the output power of the transmitter in dBm, Lc is the cable and connector loss in dB, and Ga is the antenna gain in dBi.

For AP1, the EIRP can be calculated as:

EIRP = 16 − 4 + 8 = 20 dBm

Therefore, the answer B is correct.

The likely cause of the issue of weak Wi-Fi coverage in the office is that the AP is using a directional antenna. A directional antenna is an antenna that radiates or receives radio waves more strongly in one or more directions, creating a focused beam of signal. A directional antenna can provide better coverage and performance for a specific area, but it can also create dead zones or weak spots for other areas. The other options are incorrect because they either do not affect the Wi-Fi coverage or do not match the scenario. References: https://www.arubanetworks.com/techdocs/ArubaOS_86_Web_Help/Content/arubaos-solutions/wlan-rf/rf-fundamentals.htm https://www.arubanetworks.com/techdocs/ArubaOS_86_Web_Help/Content/arubaos-solutions/wlan-rf/antennas.htm

configures DHCP snooping on the switch and enables it for VLANs 100, 110, and 120. It also specifies the IP address of the authorized DHCP server and sets the ports connected to the server as trusted. This prevents any unauthorized DHCP server from providing invalid configuration data to the clients on those VLANs. Option B also enables DHCP option-82, which adds information about the switch port and VLAN to the DHCP packets, allowing for more granular control and logging of DHCP transactions.

https://www.arubanetworks.com/techdocs/central/2.5.8/content/aos10x/aos10x-overview/aos10-kms-workflow.htm

OFDMA (Orthogonal Frequency Division Multiple Access) is a technology that can minimize client latency in a high-density environment by eliminating contention overhead by dedicating subcarriers to clients. OFDMA allows multiple clients to transmit simultaneously on different subcarriers within the same channel, reducing contention and increasing efficiency. MU-MIMO (Multi-User Multiple Input Multiple Output) is a technology that allows multiple clients to transmit simultaneously on different spatial streams within the same channel, but it does not eliminate contention overhead. QWMM (Quality of Service Wireless Multimedia) is a technology that prioritizes traffic based on four access categories, but it does not eliminate contention overhead. Channel Bonding is a technology that combines two adjacent channels into one wider channel, increasing bandwidth but not eliminating contention overhead. References: https://www.arubanetworks.com/assets/ds/DS_AP510Series.pdf https://www.arubanetworks.com/assets/wp/WP_WiFi6.pdf

The reason is that the Inter-Switch Link Protocol (ISLP) is a protocol that enables VSX stack join and synchronization between two VSX peer switches. ISLP uses a hello interval to exchange control messages between the switches.

The hello interval is a parameter that specifies the time interval between sending hello messages. The default value of the hello interval is 1 second. The hello interval can be configured from 1 second to 10 seconds.

https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6728/index.html

QoS stands for Quality of Service and is a mechanism that allows network devices to prioritize and differentiate traffic based on certain criteria, such as application type, source, destination, etc 3 .  QoS involves identifying specific traffic for special treatment and applying policies and actions to improve its performance or meet certain service level agreements (SLAs) 3 .  QoS can help network devices to manage congestion, delay, jitter, packet loss, bandwidth allocation, etc., for different types of traffic 3 .  QoS can be implemented at various layers of the network stack and across different network domains. References:  3   https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/qos/configuration/15-mt/qos-15-mt-book/qos-overview.html

LLDP-MED (Link Layer Discovery Protocol – Media Endpoint Discovery) is specifically designed to extend standard LLDP functionality for media endpoints such as VoIP phones . On AOS-CX switches, LLD P-MED can advertise network-policy information and power-related information directly to a connected IP telephone.

HPE Aruba Networking documents that the LLDP-MED network-policy TLV allows endpoints and network devices to exchange the voice VLAN ID, IEEE 802.1p priority, and DSCP values associated with voice applications. This enables a connected VoIP phone to automatically obtain the QoS information required for correct voice traffic classification. Aruba Networking

LLDP-MED also supports PoE information through MED TLVs . AOS-CX provides the lldp med poe capability to advertise Power over Ethernet Data Link Layer Classification information and, where configured, PoE priority information. Aruba Networking

Standard LLDP provides basic device discovery but LLDP-MED adds the media-specific extensions required here. LACP negotiates link aggregation and has no role in voice endpoint provisioning. CDP is Cisco ' s proprietary discovery protocol and is not the standards-based AOS-CX mechanism specified for this purpose.

Therefore, LLDP-MED is the protocol that satisfies both the DSCP/QoS and PoE provisioning requirements.

Study Guide Topics: LLDP-MED, VoIP Endpoint Provisioning, Network Policy TLVs, DSCP, 802.1p, PoE, AOS-CX Device Discovery.

The capability that enables plug-and-play provisioning of access points in an HPE Aruba network is the UCC Service. The UCC Service is a cloud-based service that allows the access points to automatically discover and connect to the Aruba Central management platform without any manual intervention. The UCC Service also provides zero-touch configuration, firmware updates, and monitoring for the access points 1 .

The other options are incorrect because:

B. LLDP-MED: LLDP-MED is a protocol that enhances the interoperability between network devices and IP phones. It does not enable plug-and-play provisioning of access points 2 .

C. SRTP: SRTP is a protocol that provides encryption and authentication for voice and video traffic. It does not enable plug-and-play provisioning of access points 3 .

D. CSMA: CSMA is a protocol that regulates how devices share a common medium, such as a wireless channel. It does not enable plug-and-play provisioning of access points.

Client IP address : This factor can be used to determine if the client is on the same VLAN as the AP or not. If the client IP address is on the same VLAN as the AP, then the client traffic is bridged locally.  If the client IP address is on a different VLAN than the AP, then the client traffic is forwarded to the gateway cluster through a secure tunnel  1 2 .

Client VLAN : This factor can be used to determine if the client belongs to a specific VLAN or not.  If the client belongs to a specific VLAN, then the client traffic is forwarded to that VLAN based on its IP address and security profile  1 2 .

The show aaa authentication port-access interface all client-status command displays the status of all clients authenticated by port-based access control on all interfaces. The output includes the MAC address, user role, VLAN ID, and session timeout for each client. This command can be used to examine information on which role the guest user has been assigned by the AOS-CX switch. References: https://techhub.hpe.com/eginfolib/Aruba/OS-CX_10.04/5200-6692/GUID-9B8F6E8F-9C7A-4F0D-AE7B-9D8E6C5B6A7F.html

The standard that is supported by some Aruba APs and can enable a customer to accurately locate wireless client devices within a few meters is A. 802.11mc.

802.11mc is an IEEE standard that enables computing devices to measure the distance to nearby Wi-Fi access points using a technique called Fine Timing Measurement (FTM). FTM uses precise timestamps to calculate the round-trip time of Wi-Fi frames between the device and the access point, and then converts it to a distance estimate. By using multiple access points and triangulation methods, the device can determine its location with high accuracy 1 .

According to the Aruba document 802.11mc Support , this feature is supported on 500 Series, 510 Series, 530 Series, 550 Series, 560 Series and 570 Series access points. These APs act as FTM responders to time measurement queries sent from a client. To configure the AP to send FTM responses, you need to enable the ftm-responder-enable parameter in the WLAN SSID profile 1 .

QoS concept:  Class of Service  Definition: 3) A method for classifying network traffic using access categories based on the IEEE 802.11e QoS standards

QoS concept:  Differentiated services  Definition: 2) A method for classifying network traffic at layer-3 or marking packets with one of 64 different service classes

QoS concept:  WMM  Definition: 4) A method for classifying network traffic using access categories based on the IEEE 802.11e QoS standards

Authentication survivability is a feature that allows the device to remain operational when a remote link failure occurs between a Gateway cluster and a RADIUS server that is either in the cloud or a datacenter. Authentication survivability enables the Gateway cluster to cache successful authentication requests from the RADIUS server and use them to authenticate clients when the RADIUS server is unreachable. Authentication survivability also allows clients to use MAC caching or MAC authentication bypass (MAB) methods to access the network when the RADIUS server is down. References: https://www.arubanetworks.com/assets/tg/TG_AuthSurvivability.pdf

The correct answer is B. An event log message is created.

The do-not-disable parameter is used to prevent the switch from disabling the port when a loop is detected by the loop-protect feature. Instead, the switch will generate an event log message that indicates the port number and the VLAN ID where the loop was detected. The switch will also send a trap to the SNMP manager, if configured 1 .

The other options are incorrect because:

A. Port status will not be validated once status is cleared. The port will remain enabled even if a loop is detected, unless the loop-protect action is changed to tx-disable or tx-rx-disable 1 .

C. The network analytics engine will not be triggered by a loop detection. The network analytics engine is a feature that allows users to monitor and troubleshoot network issues using scripts and agents 2 .

D. Port status LED will not blink in amber with 100Hz. The port status LED will indicate the normal port status, such as link speed and activity, regardless of the loop detection 3 .

Wi-Fi 6 is an industry certification for products that support the new wireless standard 802.11ax, also known as “high-efficiency wireless”. Wi-Fi 6 offers increased capacities, improved resource utilization and higher throughput speeds than previous standards.

Option B: ClientMatch

This is because option B shows how to use ClientMatch to optimize the wireless performance of Wi-Fi 6 clients on a UniFi network.  ClientMatch is a feature that uses machine learning to analyze the traffic patterns of each client and assign them to the best available AP based on their location, device type, and network conditions 2 .

Therefore, option B is the best technology to implement for your customer’s issue.

1 : https://help.ui.com/hc/en-us/articles/221029967-UniFi-Network-Optimizing-Wireless-Connectivity  2 : https://help.ui.com/hc/en-us/articles/360012947634-UniFi-Network-Optimizing-Wireless-Speeds

Two parts of the solution for these requirements are Option C and Option E.

Option C is a part of the solution because it defines a policy-based routing action list named route_test, which specifies the next hop IP address as 10.1.1.253 for the matching traffic. This is the new default route that the user wants to use for the subnet 10.2.250.0/24. The interface null parameter indicates that the traffic will be routed to the next hop without using a specific interface 1 .

Option E is a part of the solution because it applies the policy-based routing action list route_test to the VLAN interface 250, which has an IP address of 10.2.250.1/24. This is the subnet that the user wants to test the new default route for. The apply policy command enables policy-based routing on the interface and associates it with the action list 2 .

Option A is not a part of the solution because it defines a policy-based routing action list named route_test, but does not specify the next hop IP address as 10.1.1.253, which is the new default route that the user wants to use. Instead, it specifies a next hop IP address of 10.1.1.254, which is different from the requirement.

Option B is not a part of the solution because it defines a policy-based routing action list named route_test, but does not specify any next hop IP address at all, which is necessary for policy-based routing to work. Instead, it specifies an interface null parameter without any IP address, which is invalid.

Option D is not a part of the solution because it applies the policy-based routing action list route_test to the VLAN interface 200, which has an IP address of 10.2.200.1/24. This is not the subnet that the user wants to test the new default route for, but a different subnet that should not be affected by this change.

OCSP is a protocol that allows clients to query the CA or a trusted responder for the status of a specific certificate.  OCSP requests and responses are smaller and faster than CRLs, and they can provide real-time information about the revocation status of a certificate 1 2 . CRLs are lists of all revoked certificates that are downloaded from the CA.  CRLs can present issues, as they can become outdated and have to be downloaded frequently 1 3 .  Therefore, OCSP reduces latency between the time a certificate is revoked and validation reflects this status. References:  1  https://sectigostore.com/blog/ocsp-vs-crl-whats-the-difference/  2  https://www.keyfactor.com/blog/what-is-a-certificate-revocation-list-crl-vs-ocsp/  3   https://www.fortinet.com/resources/cyberglossary/ocsp

PAPI is the protocol that is used to establish tunnels between the CX switch and the Aruba Gateway for Dynamic Segmentation 1 .  By default, PAPI uses a simple checksum to verify the integrity of the messages, but it does not encrypt the payload 2 . This could expose the network to spoofing or replay attacks by malicious actors.  To address this situation, the administrator must enable Enhanced PAPI security, which uses AES-256 encryption and HMAC-SHA1 authentication to protect the tunnel traffic 2 .  Enhanced PAPI security can be enabled on the CX switch by using the command  system papi enhanced-security enable 3 . This will ensure that the tunnels built between the CX switch and the Aruba Gateway are encrypted and authenticated.

https://www.howtogeek.com/794724/what-is-wi-fi-calling/  2 : https://www.networkcomputing.com/networking/your-network-optimized-wifi-calling  3 : https://www.arubanetworks.com/techdocs/AOS-CX/10.10/HTML/monitoring_6300-6400/Content/Chp_LEDs/fro-pan-led-630.htm

Loop protection is a feature that detects and prevents loops in layer 2 networks. Loop protection can be enabled on ports, LAGs, or VLANs. When loop protection is enabled, the switch sends periodic loop protection messages on the interface and expects to receive them back.  If a loop protection message is received back on the same interface, it indicates a loop and the switch takes an action to disable the interface or block traffic on it 3 . The loop-protect re-enable-timer command is used to configure the length of time the switch waits before re-enabling an interface that was disabled due to loop detection.  The default value is 0, which means that the interface remains disabled until manually re-enabled 3 .  To automate the process of resuming the port operational state once a loop on a client port is cleared, the loop-protect re-enable-timer command can be used with a non-zero value on the interface range that includes the client ports 3 . Therefore, answer C is correct.

AOS 10 Gateways can have the following personas: Mobility, Branch, and VPN Concentrator 1  However, the Mobility persona is only available when configuring a Gateway-only group, which is a group that contains only one gateway device 2  The Mobility persona provides Overlay WLAN and (or) wired LAN functionalities for campus networks 1  The Branch persona provides the Aruba Instant OS and SD-Branch (LAN + WAN) functionality for branch and microbranch networks 1  The VPN Concentrator persona provides VPN termination and routing functionality for remote access networks 3  The Edge persona is not a valid option, as it is not a supported device persona for AOS 10 Gateways.