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

Auto-site clustering is a feature that allows gateways in the same site and group to form a cluster automatically. However, this mode does not support VRRP IP addresses, which are required for dynamic authorization (CoA) from ClearPass Policy Manager (CPPM) to the gateways. Dynamic authorization is a mechanism that allows CPPM to change the attributes or status of a client session on the gateways without requiring re-authentication. This is useful for applying policies, roles, or bandwidth limits based on various conditions. Without VRRP IP addresses, CPPM would not be able to send CoA messages to the correct gateway in case of a failover event, resulting in inconsistent or incorrect client behavior.

To enable VRRP IP addresses for dynamic authorization, you need to set up gateway clusters manually and assign a VRRP VLAN and a VRRP IP address to each cluster. This way, CPPM can use the VRRP IP address as the NAS IP address for RADIUS communications and CoA messages. The VRRP IP address will remain the same even if the active gateway in the cluster changes due to a failover event, ensuring seamless operations. You can find more information about how to set up gateway clusters manually and configure VRRP IP addresses in the Gateway Cluster Deployment - Aruba page and the ClearPass Policy Manager User Guide1.

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 .

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.