HPE6-A84 Exam Dumps : Aruba Certified Network Security Expert Written Exam

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.

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 .

Alert duration and threshold settings are used to control how often and under what conditions email notifications are sent for gateway IDS/IPS events 1. By adjusting these settings, the customer can reduce the frequency of repeat email notifications for the same threat, while still being informed of any critical or new threats.

To adjust the alert duration and threshold settings in Aruba Central, the customer can follow these steps 1:

• In the Aruba Central app, set the filter to Global, a group, or a device.
• Under Analyze, click Alerts & Events.
• Click the Config icon to open the Alert Severities & Notifications page.
• Select the Gateway IDS/IPS tab to view the alert categories and severities for gateway IDS/IPS events.
• Click on an alert category to expand it and view the alert duration and threshold settings for each severity level.
• Enter a value in minutes for the alert duration. This is the time period during which the alert is active and email notifications are sent.
• Enter a value for the alert threshold. This is the number of times the alert must be triggered within the alert duration before an email notification is sent.
• Click Save.

By increasing the alert duration and/or threshold values, the customer can reduce the number of email notifications for recurring threats, as they will only be sent when the threshold is reached within the duration. For example, if the customer sets the alert duration to 60 minutes and the alert threshold to 10 for a Critical severity level, then an email notification will only be sent if the same threat occurs 10 times or more within an hour.