HP HPE6-A84 Aruba Certified Network Security Expert Written Exam Exam Practice Test

Dynamic authorization is a feature that allows CPPM to send change of authorization (CoA) or disconnect messages to the MC to modify or terminate a user session based on certain conditions or events 1. Dynamic authorization uses the RFC 3576 protocol, which is an extension of the RADIUS protocol 2.

To enable dynamic authorization on the MC, you need to configure the IP address and UDP port of the CPPM server as the RFC 3576 server on the MC 3. The default UDP port for RFC 3576 is 3799, but it can be changed on the CPPM server . The MC and CPPM must use the same UDP port for dynamic authorization to work properly 3.

In this scenario, the MC is configured with the IP address of the CPPM server (10.47.47.8) as the RFC 3576 server, but it is using the default UDP port of 3799. However, according to the exhibit, the CPPM server is using a different UDP port of 1700 for dynamic authorization . This mismatch causes the CoA requests from CPPM to fail on the MC, as shown by the statistics .

To fix this issue, you need to change the UDP port in the MCs’ RFC 3576 server config to match the UDP port used by CPPM, which is 1700 in this case. Alternatively, you can change the UDP port in CPPM to match the default UDP port of 3799 on the MC. Either way, you need to ensure that both devices use the same UDP port for dynamic authorization 3 .

According to the AOS 10 documentation1, WIDS is a feature that monitors the radio spectrum for the presence of unauthorized, rogue access points and the use of wireless attack tools. WIDS can be configured at different levels, such as low, medium, high, or custom. The higher the level, the more checks are enabled and the more alerts are generated. However, not all checks are equally relevant or indicative of real threats. Some checks may generate false positives or unnecessary alerts that can overwhelm the administrators and reduce the effectiveness of WIDS.

Therefore, one step that could be recommended to reduce the number of email notifications is to change the WIDS level to custom, and enable only the checks most likely to indicate real threats. This way, the administrators can fine-tune the WIDS settings to suit their network environment and security needs, and avoid getting flooded with irrelevant or redundant alerts. Option C is the correct answer.

Option A is incorrect because sending the email notifications directly to a specific folder and only checking the folder once a week is not a good practice for security management. This could lead to missing or ignoring important alerts that require immediate attention or action. Moreover, this does not solve the problem of getting too many emails in the first place.

Option B is incorrect because disabling email notifications for Rogue AP, but leaving the Infrastructure Attack Detected and Client Attack Detected notifications on, is not a sufficient solution. Rogue APs are unauthorized access points that can pose a serious security risk to the network, as they can be used to intercept or steal sensitive data, launch attacks, or compromise network performance. Therefore, disabling email notifications for Rogue APs could result in missing critical alerts that need to be addressed.

Option D is incorrect because disabling just the Rogue AP and Client Attack Detected alerts, as they overlap with the Infrastructure Attack Detected alert, is not a valid assumption. The Infrastructure Attack Detected alert covers a broad range of attacks that target the network infrastructure, such as deauthentication attacks, spoofing attacks, denial-of-service attacks, etc. The Rogue AP and Client Attack Detected alerts are more specific and focus on detecting and classifying rogue devices and clients that may be involved in such attacks. Therefore, disabling these alerts could result in losing valuable information about the source and nature of the attacks.

The correct answer is D. Enabling alerts and email notifications for events related to gateway IPS engine utilization and errors.

Gateway IDS/IPS is a feature that allows the Aruba gateways to monitor and block malicious or unwanted traffic based on predefined or custom rules 1. The Fail Strategy is a setting that determines how the gateways handle traffic when the IPS engine fails or crashes 2. The Block option means that the gateways will stop forwarding traffic until the IPS engine recovers, while the Bypass option means that the gateways will continue forwarding traffic without inspection 2.

The Block option provides more security, but it also increases the risk of network outages if the IPS engine fails frequently or for a long time 2. To minimize this risk, it is recommended to enable alerts and email notifications for events related to gateway IPS engine utilization and errors 3. This way, the network administrators can be informed of any issues with the IPS engine and take appropriate actions to restore or troubleshoot it 3.

The other options are not correct or relevant for this issue:

• Option A is not correct because configuring a relatively high threshold for the gateway threat count alerts would not help minimize unexpected outages caused by using the Block option. The gateway threat count alerts are used to notify the network administrators of the number of threats detected by the IPS engine, but they do not affect how the gateways handle traffic when the IPS engine fails 4.
• Option B is not correct because making sure that the gateways have formed a cluster and operate in default gateway mode would not help minimize unexpected outages caused by using the Block option. The gateway cluster mode is used to provide high availability and load balancing for the gateways, but it does not affect how the gateways handle traffic when the IPS engine fails . The default gateway mode is used to enable routing and NAT functions on the gateways, but it does not affect how the gateways handle traffic when the IPS engine fails .
• Option C is not correct because setting the IDS or IPS policy to the least restrictive option, Lenient, would not help minimize unexpected outages caused by using the Block option. The IDS or IPS policy is used to define what rules are applied by the IPS engine to inspect and block traffic, but it does not affect how the gateways handle traffic when the IPS engine fails 2. The Lenient option contains fewer and older rules than the Moderate or Strict options, which means that it provides less security and more false negatives .

AppRF and WebCC are features that allow the MCs to classify and control application traffic and web content based on predefined or custom categories 12. These features are required to meet the scenario requirements of denying access to all high-risk websites and denying access to the WLAN for a period of time if they send any SSH or Telnet traffic.

To enable AppRF and WebCC, you need to check the following settings:

• On the global level, you need to enable AppRF and WebCC under Configuration > Services > AppRF and Configuration > Services > WebCC, respectively 12.
• On the role level, you need to enable AppRF and WebCC under Configuration > Security > Access Control > Roles > medical-mobile > AppRF and Configuration > Security > Access Control > Roles > medical-mobile > WebCC, respectively 12.
• You also need to make sure that the MCs have valid licenses for AppRF and WebCC, which are included in the ArubaOS PEFNG license 3.

To configure user-based tunneling (UBT) on an AOS-CX switch, you need to specify the IP addresses of the mobility gateways that will receive the tunneled traffic from the switch 1. The primary controller is the preferred gateway for the switch to establish a tunnel, and the backup controller is the alternative gateway in case the primary controller fails or becomes unreachable 1. The IP addresses of the gateways should be their system IP addresses, which are used for inter-controller communication and cluster discovery 2.

In this scenario, the customer has a gateway cluster with two gateways, each with a system IP address on VLAN 4085. Therefore, the switch should use these system IP addresses as the primary and backup controllers for UBT. The IP addresses of the gateways on VLAN 20 and VLAN 4094 are not relevant for UBT, as they are used for user traffic and WAN connectivity, respectively 2. The VRRP IP address on VLAN 20 is also not applicable for UBT, as it is a virtual IP address that is not associated with any specific gateway 3.

Therefore, the best option is to use 10.20.4.21 as the primary controller and 10.20.4.22 as the backup controller for UBT on the switch. This will ensure high availability and cluster discovery for the tunneled traffic from the switch to the gateway cluster 12.

A beacon is a type of network traffic that is sent from a compromised device to a command and control (C2) server, which is a remote system that controls the malicious activities of the device . A beacon is used to establish and maintain communication between the device and the C2 server, as well as to receive instructions or exfiltrate data .

A common characteristic of a beacon is that it is periodic, meaning that it is sent at regular intervals, such as every few minutes or hours . This helps the C2 server to monitor the status and availability of the device, as well as to avoid detection by network security tools .

Another common characteristic of a beacon is that it is small and identically sized, meaning that it contains minimal or fixed amount of data, such as a simple acknowledgment or a random string . This helps the device to conserve bandwidth and resources, as well as to avoid detection by network security tools .

This is because a downloadable user role (DUR) is a feature that allows the switch to use a central ClearPass server to download user-roles to the switch for authenticated users12 A DUR can contain various attributes and rules that define the access level and privileges of the user, such as VLAN, ACL, PoE, reauthentication period, etc3 A DUR can also be customized and updated on the ClearPass server without requiring any changes on the switch1

A DUR can be used to create a “provision” role that allows users to enroll new wired clients in Intune. The “provision” role can have limited access that only lets them enroll and receive certificates from the Intune service. The “provision” role can also have rules that restrict the Internet access of the users to only the necessary sites, such as the Intune portal and the certificate authority. The rules can be based on IPv4 or IPv6 addresses, depending on the network configuration and preference2

A. Configuring the rules for the “provision” role with IPv6 addresses, which tend to be more stable. This is not a valid recommendation because it does not address how to create and apply the “provision” role on the switch. Moreover, IPv6 addresses do not necessarily tend to be more stable than IPv4 addresses, as both protocols have their own advantages and disadvantages4

B. Enabling tunneling to the MCs on the “provision” role and then setting up the privileges on the MCs. This is not a valid recommendation because it does not explain how to enable tunneling or what MCs are. Moreover, tunneling is a technique that encapsulates one network protocol within another, which adds complexity and overhead to the network communication5

D. Assigning the “provision” role to a VLAN and then setting up the rules within a Layer 2 access control list (ACL). This is not a valid recommendation because it does not explain how to assign a role to a VLAN or how to create a Layer 2 ACL on the switch. Moreover, a Layer 2 ACL is limited in its filtering capabilities, as it can only match on MAC addresses or Ethernet types, which might not be sufficient for restricting Internet access to specific sites

The UBT solution requires that the VLAN assignments for the wired clients are done by the gateway, not by the switch. Therefore, the role configurations on the gateways should not have any VLAN assignments, as they would override the VLAN 20 that is specified in the enforcement profile. Instead, the role configurations should only have policies that define the access rights for the clients in the “eth-internet” role. This way, the gateway can assign the clients to VLAN 20 and apply the appropriate policies based on their role1

The UBT solution requires that the edge ports on the switches are configured in VLAN trunk mode, not access mode. This is because the UBT solution uses a special VLAN (VLAN 4095 by default) to encapsulate the user traffic and tunnel it to the gateway. The edge ports need to allow this VLAN as well as any other VLANs that are used for management or control traffic. Therefore, the edge ports should be configured as VLAN trunk ports and allow the necessary VLANs1

The correct answer is B. Create a new VLAN on the AOS-CX switch and configure that VLAN as the UBT client VLAN.

User-based tunneling (UBT) is a feature that allows the AOS-CX switches to tunnel the traffic from wired clients to a mobility gateway cluster, where they can be assigned a role and a VLAN based on their authentication and authorization 1. To enable UBT, the switches need to have a UBT zone configured with the IP addresses of the gateways, and a UBT client VLAN configured with the ubt-client-vlan command 2.

The UBT client VLAN is a special VLAN that is used to encapsulate the traffic from the tunneled clients before sending it to the gateways. The UBT client VLAN must be different from any other VLANs used on the switch or the network, and it must not be assigned to any ports or interfaces on the switch 2. The UBT client VLAN is only used internally by the switch for UBT, and it is not visible to the clients or the gateways.

In this scenario, the customer wants to tunnel the clients that pass user authentication to the gateway cluster, where they will be assigned to VLAN 20. Therefore, the switch must have a UBT client VLAN configured that is different from VLAN 20 or any other VLANs on the network. For example, the switch can use VLAN 4000 as the UBT client VLAN, as shown in one of the web search results 3. The switch must also have a UBT zone configured with the system IP addresses of the gateways as the primary and backup controllers, as explained in question 3.

The other options are not correct or relevant for this issue:

• Option A is not correct because assigning VLAN 20 as the access VLAN on any edge ports to which tunneled clients might connect would conflict with UBT. The access VLAN is the VLAN that is assigned to untagged traffic on a port, and it is used for local switching on the switch 4. If VLAN 20 is assigned as the access VLAN, then the traffic from the clients will not be tunneled to the gateways, but rather switched locally on VLAN 20. This would defeat the purpose of UBT and cause inconsistency in role and VLAN assignment.
• Option C is not correct because VIA licenses are not required for UBT. VIA licenses are required for enabling VPN services on Aruba Mobility Controllers for remote access clients using Aruba Virtual Intranet Access (VIA) software . VIA licenses are not related to UBT or wired clients.
• Option D is not correct because changing the port-access auth-mode mode to client-mode on any edge ports to which tunneled clients might connect would not affect UBT. The port-access auth-mode mode determines how a port handles authentication requests from multiple clients connected to a single port . Client-mode is the default mode that allows only one client per port, while multi-client-mode allows multiple clients per port. The port-access auth-mode mode does not affect how UBT works or how traffic is tunneled from a port.

The subnet mask in rule 3 of the “medical-mobile” policy is currently 255.255.252.0, which means that the rule denies access to the 10.1.12.0/22 subnet as well as the adjacent 10.1.16.0/22 subnet 1. This is not consistent with the scenario requirements, which state that only the 10.1.12.0/22 subnet should be denied access, while the rest of the 10.1.0.0/16 range should be permitted access.

To fix this issue, the subnet mask in rule 3 should be changed to 255.255.248.0, which means that the rule only denies access to the 10.1.8.0/21 subnet, which includes the 10.1.12.0/22 subnet 1. This way, the rule matches the scenario requirements more precisely.

A custom NAE script is a Python script that defines the monitors, the alert-trigger logic, and the remedial actions for an NAE agent. A monitor is a URI that specifies the data source and the data type that the NAE agent should collect and analyze. For example, to monitor the ARP inspection statistics on a VLAN, the monitor URI would be something like this:

where is the ID of the VLAN to be monitored.

To allow the admins to select the correct VLAN ID for the agent to monitor when they create the agent, you need to define a VLAN ID parameter in the NAE script. A parameter is a variable that can be set by the user when creating or modifying an agent. A parameter can be referenced in other parts of the script by using the syntax ${parameter-name}. For example, to define a VLAN ID parameter and reference it in the monitor URI, you would write something like this:

This way, when the admins create or modify the agent, they can enter the VLAN ID that they want to monitor, and the NAE script will use that value in the monitor URI.

You can find more information about how to write custom NAE scripts and use parameters in the NAE Scripting Guide

 This is because this URI specifies the exact attribute that contains the number of access rejects from the RADIUS server, which is the information that the NAE script needs to monitor and trigger an alert.

A. /rest/v1/system/vrfs/mgmt/radius/servers/cp.acnsxtest.local/2083/tcp?attributes=authstatistics. This is not the correct URI because it returns the entire authstatistics object, which contains more information than the access rejects, such as access accepts, challenges, timeouts, etc. This might make the NAE script more complex and inefficient to parse and process the data.

B. /rest/v1/system/vrfs/mgmt/radius/servers/cp.acnsxtest.local/2083/tcp?attributes=authstatistics?attributes=access_rejects. This is not a valid URI because it has two question marks, which is a syntax error. The question mark is used to indicate the start of the query string, which can have one or more parameters separated by ampersands. The correct way to specify multiple attributes is to use a comma-separated list after the question mark, such as ?attributes=attr1,attr2,attr3.

C. /rest/v1/system/vrfs/mgmt/radius/_servers/cp.acnsxtest.local/2083/tcp. This is not a valid URI because it has an extra underscore before servers, which is a typo. The correct resource name is servers, not _servers. Moreover, this URI does not specify any attributes, which means it will return the default attributes of the RADIUS server object, such as name, port, protocol, etc., but not the authstatistics or access_rejects.

7of30

According to the AOS-CX Switches Multiple Vulnerabilities1, one of the vulnerabilities (CVE-2021-41000) affects the SSH service on AOS-CX switches. This vulnerability allows an unauthenticated remote attacker to cause a denial-of-service condition on the switch by sending specially crafted SSH packets. The impact of this vulnerability is high, as it could result in a loss of management access and network disruption. Therefore, one recommendation to make is to create a control plane ACL to limit the sources that can access the switch with SSH. This way, the switch can filter out unwanted or malicious SSH traffic and reduce the risk of exploitation.

This is because a parameter is a variable that can be defined and modified by the user or the script, and can be used to customize the behavior and output of the NAE script. A parameter can be referred to by using the syntax self ^ramsfname], where ramsfname is the name of the parameter.

By defining a parameter for the RADIUS server, you can make the NAE script more flexible and adaptable to different scenarios and switches. The parameter can be set to a default value, such as cp.acnsxtest.local, but it can also be changed by the user or the script based on the network conditions and requirements. For example, the user can select a different hostname or IP address for the monitored RADIUS server when they create an agent from the script, or the script can automatically detect and update the parameter based on the switch configuration. This way, the NAE script can monitor statistics from any RADIUS server defined on the switch without hard-coding the server name or IP address in the monitor URI.

A. Use this variable, %{radius-ipV when defining the monitor URI in the NAE agent script. This is not a valid recommendation because %{radius-ipV is not a valid variable in NAE scripts. Variables in NAE scripts are prefixed with self ^ramsfname], not with %. Moreover, radius-ipV is not a predefined variable that contains the RADIUS server name or IP address, but rather a generic term that could refer to any IP version.

C. Use a callback action to collect the name of any RADIUS servers defined on the switch at the time the agent is created. This is not a bad recommendation, but it is not as good as defining a parameter. A callback action is a feature that allows an NAE script to execute a command on the switch and collect its output for further processing or display. A callback action can be used to collect the name of any RADIUS servers defined on the switch by executing a command such as show radius-server or show running-config radius-server and parsing its output. However, a callback action might not be as fast or reliable as using a parameter, as it depends on the availability and responsiveness of the switch and its CLI.

D. Make the script editable so that admins can edit it on demand when they are creating scripts. This is not a good recommendation because making the script editable exposes it to potential errors or modifications that could affect its functionality or performance. Making the script editable also requires more effort and expertise from the admins, who might not be familiar with NAE scripting syntax or logic. Moreover, making the script editable does not future proof it, as it does not allow for dynamic changes or updates based on network conditions or requirements.

10of30

A DNS SAN (Subject Alternative Name) is an extension of the X.509 certificate standard that allows specifying additional hostnames or IP addresses that the certificate can be used for. A DNS SAN is useful for validating the identity of the server or client that presents the certificate, especially when the common name (CN) field does not match the hostname or IP address of the server or client.

In this case, the certificate has a CN of mc41.site94.example.com, which is the fully qualified domain name (FQDN) of the standalone Aruba Mobility Controller (MC). However, this CN may not match the hostname or IP address that the MC uses for the Web UI or for implementing RadSec with Aruba ClearPass Policy Manager. For example, if the MC uses a different FQDN, such as mc41.example.com, or an IP address, such as 192.168.1.41, for these purposes, then the certificate would not be valid for them. Therefore, the certificate should have a DNS SAN that includes all the possible hostnames or IP addresses that the MC may use for the Web UI and RadSec.