HPE6-A78 HP Aruba Certified Network Security Associate Exam Free Practice Exam Questions (2025 Updated)

The primary purpose of an Initialization Vector (IV) in encryption is to ensure that the same plaintext encrypted with the same encryption key will produce different ciphertext each time it is encrypted. This variability is crucial for securing repetitive data patterns and preventing certain types of cryptographic attacks, such as replay or pattern analysis attacks. The IV adds randomness to the encryption process, making it more secure by ensuring that encrypted messages are unique, even if the plaintext and key remain unchanged. This prevents attackers from deducing patterns or inferring any useful information from repeated ciphertext.

To configure the infrastructure to support network scans as part of the ClearPass Policy Manager (CPPM) solution, creating SNMPv3 users on ArubaOS-CX switches is necessary. Ensuring that the credentials for these SNMPv3 users match those configured on CPPM is crucial for enabling CPPM to perform network scans effectively. SNMPv3 provides a secure method for network management by offering authentication and encryption, which are essential for safely conducting scans that classify endpoints by type. This configuration allows CPPM to communicate securely with the switches and gather necessary data without compromising network security.

Device fingerprinting on an AOS-CX switch allows the switch to collect information about connected clients to aid in profiling and policy enforcement, often in conjunction with a solution like ClearPass Policy Manager (CPPM). The commands provided create a device fingerprinting profile named "myprofile" and enable the collection of DHCP and LLDP information:

client device-fingerprint profile myprofile: Creates a fingerprinting profile.

dhcp: Enables the collection of DHCP information (e.g., DHCP options like Option 55 for fingerprinting).

lldp: Enables the collection of LLDP (Link Layer Discovery Protocol) information (e.g., system name, description).

However, creating the profile and enabling DHCP and LLDP collection is not enough for the switch to start collecting this information from clients. The profile must be applied to the interfaces (ports) where clients are connected.

Option C, "Apply the policy to edge ports," is correct. In AOS-CX, the device fingerprinting profile must be applied to the edge ports (ports where clients connect) to enable the switch to collect DHCP and LLDP information from those clients. This is done using the command client device-fingerprint profile under the interface configuration. For example, on port 1/1/1, you would enter:

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Switch(config)# interface 1/1/1

Switch(config-if)# client device-fingerprint profile myprofile

This ensures that the switch collects DHCP and LLDP data from clients connected to the specified ports.

Option A, "Configure the switch as a DHCP relay," is incorrect. While a DHCP relay (using the ip helper-address command) is needed if the DHCP server is on a different subnet, it is not a requirement for the switch to collect DHCP information for fingerprinting. The switch can snoop DHCP traffic on the local VLAN without being a relay, as long as the profile is applied to the ports.

Option B, "Add at least one LLDP option to the policy," is incorrect. The lldp command in the fingerprinting profile already enables the collection of LLDP information. There is no need to specify individual LLDP options (e.g., system name, description) in the profile; the switch collects all available LLDP data by default.

Option D, "Add at least one DHCP option to the policy," is incorrect. The dhcp command in the fingerprinting profile already enables the collection of DHCP information, including options like Option 55 (Parameter Request List), which is commonly used for fingerprinting. There is no need to specify individual DHCP options in the profile.

The HPE Aruba Networking AOS-CX 10.12 Security Guide states:

"To enable device fingerprinting on an AOS-CX switch, create a device fingerprinting profile using the client device-fingerprint profile command, and specify the protocols to collect, such as dhcp for DHCP information and lldp for LLDP information. To start collecting data from clients, apply the profile to edge ports where clients connect using the command client device-fingerprint profile under the interface configuration. For example, interface 1/1/1 followed by client device-fingerprint profile myprofile enables fingerprinting on port 1/1/1." (Page 160, Device Fingerprinting Configuration Section)

Additionally, the HPE Aruba Networking AOS-CX 10.12 System Management Guide notes:

"The device fingerprinting profile must be applied to the ports where clients are connected to collect DHCP and LLDP information. The dhcp and lldp commands in the profile enable the collection of all relevant data for those protocols, such as DHCP Option 55 for fingerprinting, without requiring additional options to be specified." (Page 95, Device Fingerprinting Setup Section)

When a client (e.g., a Chrome browser) accesses an HTTPS server, the server presents a certificate to establish a secure connection. The client must validate the certificate to trust the server. The certificate in this scenario has the following properties:

Subject name: myhost.example.com

SAN (Subject Alternative Name): DNS: myhost.example.com; DNS: myhost1.example.com

Extended Key Usage (EKU): Server authentication

Issuer: MyCA_Signing (an intermediate CA)

The server also sends an intermediate CA certificate for MyCA_Signing, signed by MyCA (the root CA).

The client’s Trusted CA Certificate list does not include MyCA or MyCA_Signing.

Certificate Validation Process:

Name Validation: The client checks if the server’s hostname (myhost1.example.com) matches the Subject name or a SAN in the certificate. Here, the SAN includes "myhost1.example.com," so the name validation passes.

EKU Validation: The client verifies that the certificate’s EKU includes "Server authentication," which is required for HTTPS. The EKU is correctly set to "Server authentication," so this validation passes.

Chain of Trust Validation: The client builds a certificate chain from the server’s certificate to a trusted root CA in its Trusted CA Certificate list. The chain is:

Server certificate (issued by MyCA_Signing)

Intermediate CA certificate (MyCA_Signing, issued by MyCA)

Root CA certificate (MyCA, which should be in the client’s trust store) The client’s Trusted CA Certificate list does not include MyCA or MyCA_Signing, meaning the client cannot build a chain to a trusted root CA. This causes the validation to fail.

Option A, "The client does not have the correct trusted CA certificates," is correct. The client’s trust store must include the root CA (MyCA) to trust the certificate chain. Since MyCA is not in the client’s Trusted CA Certificate list, the client cannot validate the chain, and the certificate is not trusted.

Option B, "The certificate lacks a valid SAN," is incorrect. The SAN includes "myhost1.example.com," which matches the server’s hostname, so the SAN is valid.

Option C, "The certificate lacks the correct EKU," is incorrect. The EKU is set to "Server authentication," which is appropriate for HTTPS.

Option D, "The certificate lacks a valid SAN, and the client does not have the correct trusted CA certificates," is incorrect because the SAN is valid, as explained above. The only issue is the missing trusted CA certificates.

The HPE Aruba Networking AOS-CX 10.12 Security Guide states:

"For a client to trust a server’s certificate during HTTPS communication, the client must validate the certificate chain to a trusted root CA in its trust store. If the root CA (e.g., MyCA) or intermediate CA (e.g., MyCA_Signing) is not in the client’s Trusted CA Certificate list, the chain of trust cannot be established, and the client will reject the certificate. The Subject Alternative Name (SAN) must include the server’s hostname, and the Extended Key Usage (EKU) must include ‘Server authentication’ for HTTPS." (Page 205, Certificate Validation Section)

Additionally, the HPE Aruba Networking Security Fundamentals Guide notes:

"A common reason for certificate validation failure is the absence of the root CA certificate in the client’s trust store. For example, if a server’s certificate is issued by an intermediate CA (e.g., MyCA_Signing) that chains to a root CA (e.g., MyCA), the client must have the root CA certificate in its Trusted CA Certificate list to trust the chain." (Page 45, Certificate Trust Issues Section)

The AP is classified as a rogue because it is connected to your LAN and is transmitting wireless traffic with your network's default gateway's MAC address as a source MAC. In this scenario, the 'Match method = Exact match' and 'Match type = Eth-GW-wired-Mac-Table' indicates that the rogue AP has been detected by matching the Ethernet gateway's MAC address, which is on the wired network, implying that the rogue AP is connected to the corporate LAN. Since the AP does not belong to the company, its presence on the network is unauthorized and is thus classified as a rogue AP.

Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks are both designed to disrupt the availability of a network, service, or device by overwhelming it with traffic or requests. HPE Aruba Networking documentation, particularly in the context of Wireless Intrusion Prevention (WIP) and network security, often discusses these attacks to help administrators mitigate them.

DoS Attack: A DoS attack is launched from a single source (e.g., one device or IP address) and aims to overwhelm a target (e.g., a server, network, or device) with traffic, making it unavailable to legitimate users. For example, a DoS attack might flood a server with SYN packets to exhaust its resources.

DDoS Attack: A DDoS attack is a more sophisticated version of a DoS attack, where the attack is launched from multiple sources (e.g., a botnet of compromised devices). These sources work together to overwhelm the target, making the attack harder to mitigate because the traffic comes from many different IP addresses.

Option A, "A DDoS attack originates from external devices, while a DoS attack originates from internal devices," is incorrect. Both DoS and DDoS attacks can originate from external or internal devices. The distinction is not about the location of the devices but the number of sources involved.

Option B, "A DoS attack targets one server; a DDoS attack targets all the clients that use a server," is incorrect. Both DoS and DDoS attacks typically target a single entity (e.g., a server, network, or device) to disrupt its availability. They do not target "all the clients that use a server."

Option C, "A DDoS attack targets multiple devices, while a DoS is designed to incapacitate only one device," is incorrect. Both DoS and DDoS attacks usually target a single device or service to overwhelm it. The difference lies in the source of the attack, not the number of targets.

Option D, "A DDoS attack is launched from multiple devices, while a DoS attack is launched from a single device," is correct. This is the primary distinction between the two: a DDoS attack involves multiple sources (e.g., a botnet), while a DoS attack originates from a single source.

The HPE Aruba Networking Security Guide states:

"A Denial of Service (DoS) attack is launched from a single device to overwhelm a target, such as a server or network, making it unavailable to legitimate users. A Distributed Denial of Service (DDoS) attack, in contrast, is launched from multiple devices, often a botnet of compromised systems, to flood the target with traffic from many sources, making it harder to mitigate." (Page 20, DoS and DDoS Attacks Section)

Additionally, the HPE Aruba Networking AOS-8 8.11 User Guide notes:

"The Wireless Intrusion Prevention (WIP) system can detect DoS and DDoS attacks. A DoS attack originates from a single source, while a DDoS attack involves multiple sources working together to overwhelm the target, such as a server or network infrastructure." (Page 423, WIP Threat Detection Section)

When configuring an ArubaOS-CX switch to send RADIUS debug messages to a central SIEM server, it is important to correctly direct these debug outputs. The command debug radius all activates debugging for all RADIUS processes, capturing detailed logs about RADIUS operations. If the SIEM server is already defined on the switch for logging purposes (as indicated by the command logging 10.5.6.12), the correct destination for these debug messages to be sent to the SIEM server would be through the syslog. This ensures that all generated logs are forwarded to the centralized server specified for logging, enabling consistent log management and analysis. Using syslog as the destination leverages the existing logging setup and integrates seamlessly with the network's centralized monitoring systems.

HPE Aruba Networking ClearPass Policy Manager (CPPM) uses device profiling to classify endpoints, and one of its passive profiling methods involves analyzing DHCP traffic. DHCP fingerprinting is a technique where ClearPass examines the DHCP packets sent by a client, particularly the DHCP Discover packet, to identify the device’s operating system or type based on specific attributes.

Option A, "It can determine information such as the endpoint OS from the order of options listed in Option 55 of a DHCP Discover packet," is correct. DHCP Option 55 (Parameter Request List) is a field in the DHCP Discover packet where the client specifies the list of DHCP options it requests from the server. The order and combination of these options are often unique to specific operating systems or device types (e.g., Windows, Linux, macOS, or IoT devices). ClearPass maintains a database of DHCP fingerprints and matches the Option 55 data against this database to classify the endpoint.

Option B, "It can respond to a client’s DHCP Discover with different DHCP Offers and then analyze the responses," is incorrect because ClearPass does not act as a DHCP server or send DHCP Offers. It passively snoops DHCP traffic rather than actively responding to DHCP requests.

Option C, "It can snoop DHCP traffic to register the clients’ IP addresses," is partially correct in that ClearPass does snoop DHCP traffic, but the purpose is not just to register IP addresses for HTTP probing. While ClearPass can use IP addresses for active probing (e.g., HTTP or SNMP), the question specifically asks about using DHCP to classify, which is done via fingerprinting, not IP registration.

Option D, "It can alter the DHCP Offer to insert itself as a proxy gateway," is incorrect because ClearPass does not modify DHCP packets or act as a proxy gateway. This is not a function of ClearPass in the context of DHCP-based profiling.

The HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide states:

"ClearPass can profile devices using DHCP fingerprinting, a passive profiling method. When a device sends a DHCP Discover packet, ClearPass examines the packet’s attributes, including the order of options in DHCP Option 55 (Parameter Request List). The combination and order of these options are often unique to specific operating systems or device types. ClearPass matches these attributes against its DHCP fingerprint database to classify the device (e.g., identifying a device as a Windows 10 laptop or an Android phone)." (Page 247, DHCP Fingerprinting Section)

Additionally, the ClearPass Device Insight Data Sheet notes:

"DHCP fingerprinting allows ClearPass to passively collect device information without interfering with network traffic. By analyzing DHCP Option 55, ClearPass can accurately determine the device’s operating system and type, enabling precise policy enforcement." (Page 3)

The benefit of Opportunistic Wireless Encryption (OWE) is that it allows anyone to connect, but it provides better protection against eavesdropping than a traditional open network. OWE is a type of wireless security specified in the WPA3 standard that offers encrypted communication without the complexity of a full authentication process, thereby securing data on networks that would otherwise be open and unencrypted.

In an HPE Aruba Networking AOS-8 architecture with a Mobility Master (MM), Mobility Controllers (MCs), and campus APs (CAPs), the WLAN is configured to use Tunnel forwarding mode and WPA3-Enterprise security. In Tunnel mode, all user traffic from the APs is encapsulated in a GRE tunnel and sent to the MC, which then forwards the traffic to the appropriate VLAN. The WLAN is assigned to VLAN 301, and the core routing switches act as the default router for wireless user traffic.

Tunnel Forwarding Mode: In this mode, the AP does not directly place user traffic onto the wired network. Instead, the AP tunnels all user traffic to the MC over a GRE tunnel. The MC then decapsulates the traffic and places it onto the wired network in the specified VLAN (VLAN 301 in this case). This means the VLAN tagging for user traffic occurs at the MC, not at the AP.

VLAN 301 Assignment: Since the WLAN is assigned to VLAN 301, the MC will tag user traffic with VLAN 301 when forwarding it to the wired network. The core routing switches, acting as the default router, need to receive this traffic on VLAN 301 to route it appropriately.

Therefore, VLAN 301 needs to be carried on the links between the MC ports and the core routing switches, as this is where the MC forwards the user traffic after decapsulating it from the GRE tunnel.

Option A, "Only links on the path between APs and the core routing switches," is incorrect because, in Tunnel mode, the APs do not directly forward user traffic to the wired network. The traffic is tunneled to the MC, so the links between the APs and the core switches do not need to carry VLAN 301 for user traffic (though they may carry other VLANs for AP management).

Option B, "Only links on the path between APs and the MC," is incorrect for the same reason. The GRE tunnel between the AP and MC carries encapsulated user traffic, and VLAN 301 tagging occurs at the MC, not on the AP-to-MC link.

Option C, "All links in the campus LAN to ensure seamless roaming," is incorrect because VLAN 301 only needs to be present where the MC forwards user traffic to the wired network (i.e., between the MC and the core switches). Extending VLAN 301 to all links is unnecessary and could introduce security or scalability issues.

Option D, "Only links between MC ports and the core routing switches," is correct because the MC places user traffic onto VLAN 301 and forwards it to the core switches, which act as the default router.

The HPE Aruba Networking AOS-8 8.11 User Guide states:

"In Tunnel forwarding mode, the AP encapsulates all user traffic in a GRE tunnel and sends it to the Mobility Controller (MC). The MC decapsulates the traffic and forwards it to the wired network on the VLAN assigned to the WLAN. For example, if the WLAN is assigned to VLAN 301, the MC tags the user traffic with VLAN 301 and sends it out of its wired interface to the upstream switch. Therefore, the VLAN must be configured on the links between the MC and the upstream switch or router that acts as the default gateway for the VLAN." (Page 275, Tunnel Forwarding Mode Section)

Additionally, the HPE Aruba Networking Wireless LAN Design Guide notes:

"When using Tunnel mode, the VLAN assigned to the WLAN must be carried on the wired links between the Mobility Controller and the default router for the VLAN. The links between the APs and the MC do not need to carry the user VLAN, as all traffic is tunneled to the MC, which handles VLAN tagging." (Page 52, VLAN Configuration Section)

The scenario involves an AOS-8 controller-based solution with a WPA3-Enterprise WLAN using HPE Aruba Networking ClearPass Policy Manager (CPPM) for authentication. The company is using digital certificates for authentication (likely EAP-TLS, as it’s the most common certificate-based method for WPA3-Enterprise). A user’s Windows domain computer has certificates installed, but authentication fails. The Mobility Controller (MC) logs show Access-Rejects from CPPM, indicating that CPPM rejected the authentication attempt.

Access-Reject: An Access-Reject message from CPPM means that the authentication failed due to a policy violation, certificate issue, or other configuration mismatch. To troubleshoot, we need to find detailed information about why CPPM rejected the request.

Option C, "The Alerts tab in the authentication record in CPPM Access Tracker," is correct. Access Tracker in CPPM logs all authentication attempts, including successful and failed ones. For a failed attempt (Access-Reject), the authentication record in Access Tracker will include an Alerts tab that provides detailed reasons for the failure. For example, if the client’s certificate is invalid (e.g., expired, not trusted, or missing a required attribute), or if the user does not match a policy in CPPM, the Alerts tab will specify the exact issue (e.g., "Certificate not trusted," "User not found in directory").

Option A, "The reports generated by HPE Aruba Networking ClearPass Insight," is incorrect. ClearPass Insight is used for generating reports and analytics (e.g., trends, usage patterns), not for real-time troubleshooting of specific authentication failures.

Option B, "The RADIUS events within the CPPM Event Viewer," is incorrect. The Event Viewer logs system-level events (e.g., service crashes, NAD mismatches), not detailed authentication failure reasons. While it might log that an Access-Reject was sent, it won’t provide the specific reason for the rejection.

Option D, "The packets captured on the MC control plane destined to UDP 1812," is incorrect. Capturing packets on the MC control plane for UDP 1812 (RADIUS authentication port) can show the RADIUS exchange, but it won’t provide the detailed reason for the Access-Reject. The MC logs already show the Access-Reject, so the issue lies on the CPPM side, and Access Tracker provides more insight.

The HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide states:

"Access Tracker (Monitoring > Live Monitoring > Access Tracker) logs all authentication attempts, including failed ones. For an Access-Reject, the authentication record in Access Tracker includes an Alerts tab that provides detailed reasons for the failure. For example, in a certificate-based authentication (e.g., EAP-TLS), the Alerts tab might show ‘Certificate not trusted’ if the client’s certificate is not trusted by ClearPass, or ‘User not found’ if the user does not match a policy. This is the primary place to look for deeper insight into authentication failures." (Page 299, Access Tracker Troubleshooting Section)

Additionally, the HPE Aruba Networking AOS-8 8.11 User Guide notes:

"If the Mobility Controller logs show an Access-Reject from the RADIUS server (e.g., ClearPass), check the RADIUS server’s authentication logs for details. In ClearPass, the Access Tracker provides detailed failure reasons in the Alerts tab of the authentication record, such as certificate issues or policy mismatches." (Page 500, Troubleshooting 802.1X Authentication Section)

The correct approach for capturing packets from a wireless client in a WLAN that uses Tunnel forwarding mode and WPA3-Enterprise, managed by an Aruba Mobility Controller and Campus APs, is to use an Air Monitor (AM). An AM is specifically designed to capture wireless traffic "in the air," which means it listens to the wireless signals transmitted between devices and the access points. This method ensures that the capture includes all the necessary details while maintaining the integrity and security of the data as it is transmitted over the air. Using an Air Monitor helps in analyzing the raw wireless traffic before it gets encrypted or tunneled to the Mobility Controller, providing a clear view of the wireless client's activity and interactions. The information regarding the use of Air Monitors for packet capture in such environments can be found in the Aruba Network's official documentation and configuration guides for WLAN setups and security analysis.

HPE Aruba Networking ClearPass Policy Manager (CPPM) uses endpoint classification (profiling) to identify and categorize devices on the network, enabling policy enforcement based on device type, OS, or other attributes. CPPM supports two primary profiling methods: passive and active classification.

Passive Classification: This method involves observing network traffic that endpoints send as part of their normal operation, without CPPM sending any requests to the device. Examples include DHCP fingerprinting (analyzing DHCP Option 55), HTTP User-Agent string analysis, and TCP fingerprinting (analyzing TTL and window size). Passive classification is non-intrusive and does not generate additional network traffic.

Active Classification: This method involves CPPM sending requests to the endpoint to gather information. Examples include SNMP scans (to query device details), WMI scans (for Windows devices), and SSH scans (to gather system information). Active classification is more intrusive and may require credentials or network access to the device.

Option A, "Passive classification refers exclusively to MAC OUI-based classification, while active classification refers to any other classification method," is incorrect. Passive classification includes more than just MAC OUI-based classification (e.g., DHCP fingerprinting, TCP fingerprinting). MAC OUI (Organizationally Unique Identifier) analysis is one passive method, but not the only one. Active classification specifically involves sending requests, not just "any other method."

Option B, "Passive classification classifies endpoints based on entries in dictionaries, while active classification uses admin-defined rules to classify endpoints," is incorrect. Both passive and active classification use CPPM’s fingerprint database (not "dictionaries") to match device attributes. Admin-defined rules are used for policy enforcement, not classification, and apply to both methods.

Option C, "Passive classification is only suitable for profiling endpoints in small business environments, while enterprises should use active classification exclusively," is incorrect. Passive classification is widely used in enterprises because it is non-intrusive and scalable. Active classification is often used in conjunction with passive methods to gather more detailed information, but enterprises do not use it exclusively.

Option D, "Passive classification analyzes traffic that endpoints send as part of their normal functions; active classification involves sending requests to endpoints," is correct. This accurately describes the fundamental difference between the two methods: passive classification observes existing traffic, while active classification actively queries the device.

The HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide states:

"Passive classification analyzes traffic that endpoints send as part of their normal functions, such as DHCP requests, HTTP traffic, or TCP packets, without ClearPass sending any requests to the device. Examples include DHCP fingerprinting and TCP fingerprinting. Active classification involves ClearPass sending requests to the endpoint to gather information, such as SNMP scans, WMI scans, or SSH scans, which may require credentials or network access." (Page 246, Passive vs. Active Profiling Section)

Additionally, the ClearPass Device Insight Data Sheet notes:

"Passive classification observes network traffic generated by endpoints during normal operation, such as DHCP or HTTP traffic, to identify devices without generating additional traffic. Active classification, in contrast, sends requests to endpoints (e.g., SNMP or WMI scans) to gather detailed information, which can be more intrusive but provides deeper insights." (Page 3, Profiling Methods Section)

When troubleshooting connectivity issues for a user connecting to an AP managed by a standalone Mobility Controller (MC) in an AOS-8 architecture, detailed logs and debugs specific to the user’s client are essential. The MC provides several tools for capturing logs and debugging information, including packet captures and user-specific debug logs.

Option D, "In the MC UI’s Diagnostics > Logs pages, add a ‘user-debug’ log setting for the client's MAC address," is correct. The "user-debug" feature in the MC allows administrators to enable detailed debugging for a specific client by specifying the client’s MAC address. This generates logs related to the client’s authentication, association, role assignment, and other activities, which are critical for troubleshooting connectivity issues. The Diagnostics > Logs pages in the MC UI provide a user-friendly way to configure this setting and view the resulting logs.

Option A, "In the MC CLI, set up a control plane packet capture and filter for the client's IP address," is incorrect because control plane packet captures are used to capture management traffic (e.g., between the MC and APs or other controllers), not user traffic. Additionally, the client may not yet have an IP address if connectivity is failing, making an IP-based filter less effective.

Option B, "In the MC CLI, set up a data plane packet capture and filter for the client's MAC address," is a valid troubleshooting method but is not the best choice for getting detailed logs. Data plane packet captures are useful for analyzing user traffic (e.g., to see if packets are being dropped), but they do not provide the same level of detailed logging as the "user-debug" feature, which includes authentication and association events.

Option C, "In the MC UI’s Traffic Analytics dashboard, look for the client's IP address," is incorrect because the Traffic Analytics dashboard is used for monitoring application usage and traffic patterns, not for detailed troubleshooting of a specific client’s connectivity issues. Additionally, if the client cannot connect, it may not have an IP address or generate traffic visible in the dashboard.

The HPE Aruba Networking AOS-8 8.11 User Guide states:

"To troubleshoot issues for a specific wireless client, you can enable user-specific debugging using the ‘user-debug’ feature. In the Mobility Controller UI, navigate to Diagnostics > Logs, and add a ‘user-debug’ log setting for the client’s MAC address. This will generate detailed logs for the client, including authentication, association, and role assignment events, which can be viewed in the Logs page. For example, to enable user-debug for a client with MAC address 00:11:22:33:44:55, add the setting ‘user-debug 00:11:22:33:44:55’." (Page 512, Troubleshooting Wireless Clients Section)

Additionally, the guide notes:

"While packet captures (control plane or data plane) can be useful for analyzing traffic, the ‘user-debug’ feature provides more detailed logs for troubleshooting client-specific issues, such as failed authentication or association problems." (Page 513, Debugging Tools Section)

In an Aruba network, when setting up a WPA3-Enterprise network that also supports WPA2-Enterprise clients, you would typically configure the network to operate in a transitional mode that supports both protocols. CNSA (Commercial National Security Algorithm) mode is intended for networks that require higher security standards as specified by the US National Security Agency (NSA). However, for compatibility with WPA2 clients, which do not support CNSA requirements, you would disable CNSA mode. WPA3 can use 256-bit encryption keys, which offer a higher level of security than the 128-bit keys used in WPA2.

When an ArubaOS solution detects a rogue AP with Wireless Intrusion Prevention (WIP), the most crucial information that can help locate the rogue device is the detecting devices. This is because the detecting devices can provide the physical location or the network topology context where the rogue AP has been detected1.

The detecting devices are typically the Air Monitors (AMs) or Access Points (APs) in the network that have identified the rogue AP’s presence. These devices can provide information such as the signal strength and the direction from which the rogue AP’s signals are being received. By triangulating this information from multiple detecting devices, it becomes possible to pinpoint the physical location of the rogue AP2.

Additionally, the detecting devices can log events and alerts that can be reviewed to understand the rogue AP’s behavior, such as the channels it is operating on and the potential impact on the authorized wireless network1. This information is vital for network administrators to quickly and effectively respond to the threat posed by the rogue AP.

In contrast, the match method (A) and match type © relate to how the rogue AP is classified and identified by the system, which is useful for classification but not for physical location. The confidence level (D) indicates the system’s certainty in the classification but does not aid in locating the device2.

For an ArubaOS-CX switch enforcing 802.1X on a port without any fallback options or port-access roles configured, and where the supplicant on the connected client has not completed authentication, the only type of traffic the authenticator accepts from the client is EAP (Extensible Authentication Protocol). EAP is a universal authentication framework used in 802.1X for message exchange during the authentication process. The switch allows EAP packets because they are necessary for the client and the authentication server to perform the authentication process. This is standard behavior for 802.1X authenticators, which is to permit EAP traffic to pass through even before authentication is successful to facilitate the authentication exchange. This information is supported by the IEEE 802.1X standard and ArubaOS-CX security configuration guides.

The exhibit shows an error in the CPPM Event Viewer: "RADIUS authentication attempt from unknown NAD 10.1.10.8:1812." This indicates that a new HPE Aruba Networking Mobility Controller (MC) is attempting to send RADIUS authentication requests to HPE Aruba Networking ClearPass Policy Manager (CPPM), but CPPM does not recognize the MC as a Network Access Device (NAD), resulting in the authentication failure.

Unknown NAD Error: In CPPM, a NAD is a device (e.g., an MC, switch, or AP) that sends RADIUS requests to CPPM for authentication. Each NAD must be configured in CPPM with its IP address and a shared secret. The error "unknown NAD 10.1.10.8:1812" means that the IP address 10.1.10.8 (the source IP of the MC’s RADIUS request) is not listed as a NAD in CPPM’s configuration, so CPPM rejects the request.

Option A, "That the IP address that the MC is using to reach CPPM matches the one defined for the device on CPPM," is correct. You need to check that the MC’s IP address (10.1.10.8) is correctly configured as a NAD in CPPM. In CPPM, go to Configuration > Network > Devices, and verify that a NAD entry exists for 10.1.10.8. If the IP address does not match (e.g., due to NAT, a different interface, or a misconfiguration), CPPM will reject the request as coming from an unknown NAD.

Option B, "That the MC has valid admin credentials configured on it for logging into the CPPM," is incorrect. Admin credentials on the MC are used for management access (e.g., SSH, web UI), not for RADIUS authentication. RADIUS communication between the MC and CPPM uses a shared secret, not admin credentials.

Option C, "That the MC has been added as a domain machine on the Active Directory domain with which CPPM is synchronized," is incorrect. Adding the MC as a domain machine in Active Directory (AD) is relevant only if the MC itself is authenticating users against AD (e.g., for machine authentication), but this is not required for the MC to act as a NAD sending RADIUS requests to CPPM.

Option D, "That the shared secret configured for the CPPM authentication server matches the one defined for the device on CPPM," is incorrect in this context. While a shared secret mismatch would cause authentication failures, it would not result in an "unknown NAD" error. The "unknown NAD" error occurs before the shared secret is checked, as CPPM does not recognize the IP address as a valid NAD.

The HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide states:

"The error ‘RADIUS authentication attempt from unknown NAD ’ in the Event Viewer indicates that the IP address of the device sending the RADIUS request (e.g., a Mobility Controller) is not configured as a Network Access Device (NAD) in ClearPass. To resolve this, go to Configuration > Network > Devices in the CPPM UI, and ensure that the IP address of the device (e.g., 10.1.10.8) is added as a NAD with the correct shared secret. The IP address used by the device to reach CPPM must match the one defined in the NAD configuration." (Page 302, Troubleshooting RADIUS Issues Section)

Additionally, the HPE Aruba Networking AOS-8 8.11 User Guide notes:

"When configuring a Mobility Controller to use ClearPass as a RADIUS server, ensure that the MC’s IP address is added as a NAD in ClearPass. If ClearPass logs an ‘unknown NAD’ error, verify that the IP address the MC uses to send RADIUS requests (e.g., the source IP of the request) matches the IP address configured in ClearPass under Configuration > Network > Devices." (Page 498, Configuring RADIUS Authentication Section)

Public Key Infrastructure (PKI) relies on a trusted root Certification Authority (CA) to issue certificates. Devices and users must trust the root CA for the PKI to be effective. If a root CA certificate is not pre-installed or manually chosen to be trusted on a device, any certificates issued by that CA will not be inherently trusted by the device.