In the context of an Aruba Mobility Controller (MC) configuration, a client will receive the default role assignment if they have passed 802.1X authentication and the authentication server did not send an Aruba-User-Role Vendor Specific Attribute (VSA). The default role is assigned by the MC when a client successfully authenticates but the authentication server provides no specific role instruction. This behavior ensures that a client is not left without any role assignment, which could potentially lead to a lack of network access or access control. This default role assignment mechanism is part of Aruba's role-based access control, as documented in the ArubaOS user guide and best practices.

In ArubaOS-CX, managing and searching logs can be crucial for tracking and diagnosing issues related to network operations such as port authentication. To efficiently find logs related to port authentication, configuring a logging filter specifically for this category is highly effective.

Logging Filter Configuration: In ArubaOS-CX, you can configure logging filters to refine the logs that are collected and viewed. By setting up a filter for the 'port-access' category, you focus the logging system to only capture and display entries related to port authentication events. This approach reduces the volume of log data to sift through, making it easier to identify relevant issues.

Global Application of Filter: Applying the filter globally ensures that all relevant log messages, regardless of their origin within the switch's modules or interfaces, are captured under the specified category. This global application is crucial for comprehensive monitoring across the entire device.

Alternative Options and Their Evaluation:

Option A: Adding '-C and *-c port-access' to the 'show logging' command is not a standard command format in ArubaOS-CX for filtering logs directly through the show command.

Option C: Enabling debugging for 'portaccess' indeed increases the detail of logs but primarily serves to provide real-time diagnostic information rather than filtering existing logs.

Option D: Specifying a logging facility focuses on routing logs to different destinations or subsystems and does not inherently filter by log category like port-access.

The scenario involves an AOS-8 Mobility Controller (MC) with a WLAN where a new user group has been added. Users in this group cannot connect to the WLAN, receiving errors indicating no Internet access and inability to reach resources. Exhibit 1 shows the ClearPass Policy Manager (CPPM) Access Tracker record for one user:

CPPM sends an Access-Accept with the VSA Radius:Aruba:Aruba-User-Role user_group4.

The endpoint is classified as 'Known,' but the user cannot access resources. Exhibit 2 (not provided but described) shows that the AOS device (MC) assigned the user's client to the 'denyall' role, which likely denies all access, explaining the lack of Internet and resource access.

Analysis:

CPPM sends the Aruba-User-Role VSA with the value 'user_group4,' indicating that the user should be assigned to the 'user_group4' role on the MC.

However, the MC assigns the client to the 'denyall' role, which typically denies all traffic, resulting in no Internet or resource access.

The issue lies in why the MC did not apply the 'user_group4' role sent by CPPM.

Option A, 'The AOS device does not have the correct RADIUS dictionaries installed on it to understand the Aruba-User-Role VSA,' is incorrect. If the MC did not have the correct RADIUS dictionaries to understand the Aruba-User-Role VSA, it would not process the VSA at all, and the issue would likely affect all users, not just the new user group. Additionally, Aruba-User-Role is a standard VSA in AOS-8, and the dictionaries are built into the system.

Option B, 'The AOS device has a server derivation rule configured on it that has overridden the role sent by CPPM,' is incorrect. Server derivation rules on the MC can override roles sent by the RADIUS server (e.g., based on attributes like username or NAS-IP), but there is no indication in the scenario that such a rule is configured. If a derivation rule were overriding the role, it would likely affect more users, and the issue would not be specific to the new user group.

Option C, 'The clients rejected the server authentication on their side because they do not have the root CA for CPPM's RADIUS/EAP certificate,' is incorrect. If the clients rejected the server authentication (e.g., due to a missing root CA for CPPM's certificate), the authentication would fail entirely, and CPPM would not send an Access-Accept with the Aruba-User-Role VSA. The scenario confirms that authentication succeeded (Access-Accept was sent), so this is not the issue.

Option D, 'The role name that CPPM is sending does not match the role name configured on the AOS device,' is correct. CPPM sends the role 'user_group4' in the Aruba-User-Role VSA, but the MC assigns the client to the 'denyall' role. This suggests that the role 'user_group4' does not exist on the MC, or there is a mismatch in the role name (e.g., due to case sensitivity, typos, or underscores vs. hyphens). In AOS-8, if the role specified in the Aruba-User-Role VSA does not exist on the MC, the MC falls back to a default role, which in this case appears to be 'denyall,' denying all access. The likely problem is that the role name 'user_group4' sent by CPPM does not match the role name configured on the MC (e.g., it might be 'user-group4' or a different name).

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

'When the Mobility Controller receives an Aruba-User-Role VSA in a RADIUS Access-Accept message, it attempts to assign the specified role to the client. If the role name sent by the RADIUS server (e.g., 'user_group4') does not match a role configured on the controller, the controller will fall back to a default role, such as 'denyall,' which may deny all access. To resolve this, ensure that the role name sent by the RADIUS server matches the role name configured on the controller, accounting for case sensitivity and naming conventions (e.g., underscores vs. hyphens).' (Page 306, Role Assignment Troubleshooting Section)

Additionally, the HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide notes:

'A common issue when assigning roles via the Aruba-User-Role VSA is a mismatch between the role name sent by ClearPass and the role name configured on the Aruba device. If the role name does not match (e.g., 'user_group4' vs. 'user-group4'), the device will not apply the intended role, and the client may be assigned a default role like 'denyall,' resulting in access issues. Verify that the role names match exactly in both ClearPass and the device configuration.' (Page 290, RADIUS Role Assignment Issues Section)

:

HPE Aruba Networking AOS-8 8.11 User Guide, Role Assignment Troubleshooting Section, Page 306.

HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide, RADIUS Role Assignment Issues Section, Page 290.

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The task is to configure an AOS-CX switch to send logs to a SIEM Syslog server at IP address 10.4.13.15 using TCP port 514, with logs for events at the 'warning' severity level or above (i.e., warning, error, critical, alert, emergency). The initial command entered is:

AOS-CX(config)# logging 10.4.13.15 tcp vrf default

This command configures the switch to send logs to the Syslog server at 10.4.13.15 using TCP (port 514 is the default for TCP Syslog unless specified otherwise) and the default VRF. However, this command alone does not specify the severity level of the logs to be sent, which is a requirement of the task.

Severity Level Configuration: AOS-CX switches allow you to specify the severity level for logs sent to a Syslog server. The severity levels, in increasing order of severity, are: debug, informational, notice, warning, error, critical, alert, and emergency. The requirement is to send logs at the 'warning' level or above, meaning warning, error, critical, alert, and emergency logs should be sent, but debug, informational, and notice logs should not.

Option A, 'Specify the 'warning' severity level for the logging server,' is correct. To meet the requirement, you need to add the severity level to the logging configuration for the specific Syslog server. The command to do this is:

AOS-CX(config)# logging 10.4.13.15 severity warning

This command ensures that only logs with a severity of warning or higher are sent to the Syslog server at 10.4.13.15. Since the initial command already specified TCP and the default VRF, this additional command completes the configuration.

Option B, 'Add logging categories at the global level,' is incorrect. Logging categories (e.g., system, security, network) are used to filter logs based on the type of event, not the severity level. The requirement is about severity ('warning' or above), not specific categories, so this step is not necessary to meet the stated criteria.

Option C, 'Ask for the Syslog password and configure it on the switch,' is incorrect. Syslog servers typically do not require a password for receiving logs, and AOS-CX switches do not have a configuration option to specify a Syslog password. Authentication or encryption for Syslog (e.g., using TLS) is not mentioned in the requirements.

Option D, 'Configure logging as a debug destination,' is incorrect. Configuring a debug destination (e.g., using the debug command) is used to send debug-level logs to a destination (e.g., console, buffer, or Syslog), but the requirement is to send logs at the 'warning' level or above, not debug-level logs. Additionally, the logging command already specifies the Syslog server as the destination.

The HPE Aruba Networking AOS-CX 10.12 System Management Guide states:

'To configure a Syslog server on an AOS-CX switch, use the logging <ip-address> [tcp | udp] [vrf <vrf-name>] command to specify the server's IP address, protocol, and VRF. To filter logs by severity, add the severity <level> option to the logging command. For example, logging 10.4.13.15 tcp severity warning sends logs with a severity of warning or higher (warning, error, critical, alert, emergency) to the Syslog server at 10.4.13.15 using TCP. The default port for TCP Syslog is 514.' (Page 89, Syslog Configuration Section)

Additionally, the guide notes:

'Severity levels for logging on AOS-CX switches are, in increasing order: debug, informational, notice, warning, error, critical, alert, emergency. Specifying a severity level of 'warning' ensures that only logs at that level or higher are sent to the configured destination.' (Page 90, Logging Severity Levels Section)

:

HPE Aruba Networking AOS-CX 10.12 System Management Guide, Syslog Configuration Section, Page 89.

HPE Aruba Networking AOS-CX 10.12 System Management Guide, Logging Severity Levels Section, Page 90.

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When an authentication attempt for a user's Windows domain computer is failing on a WPA3-Enterprise WLAN and the Mobility Controller is receiving Access-Rejects, one place to look for deeper insight is the RADIUS events within the CPPM Event Viewer. ClearPass Policy Manager (CPPM) logs all RADIUS authentication events, and the Event Viewer would show detailed information about why a particular authentication attempt was rejected. This could include reasons such as incorrect credentials, expired certificates, or policy mismatches. The CPPM Event Viewer is an essential troubleshooting tool within ClearPass to diagnose authentication issues, as indicated in the ClearPass Policy Manager documentation.