HPE6-A84: Aruba Certified Network Security Expert Written

Refer to the scenario.

A customer is migrating from on-prem AD to Azure AD as its sole domain solution. The customer also manages both wired and wireless devices with Microsoft Endpoint Manager (Intune).

The customer wants to improve security for the network edge. You are helping the customer design a ClearPass deployment for this purpose. Aruba network devices will authenticate wireless and wired clients to an Aruba ClearPass Policy Manager (CPPM) cluster (which uses version 6.10).

The customer has several requirements for authentication. The clients should only pass EAP-TLS authentication if a query to Azure AD shows that they have accounts in Azure AD. To further refine the clients' privileges, ClearPass also should use information collected by Intune to make access control decisions.

The customer wants you to configure CPPM to collect information from Intune on demand during the authentication process.

What should you tell the Intune admins about the certificates issued to clients?

You are working with a developer to design a custom NAE script for a customer. You are helping the developer find the correct REST API resource to monitor.

Refer to the exhibit below.

What should you do before proceeding?

Refer to the scenario.

An organization wants the AOS-CX switch to trigger an alert if its RADIUS server (cp.acnsxtest.local) rejects an unusual number of client authentication requests per hour. After some discussions with other Aruba admins, you are still not sure how many rejections are usual or unusual. You expect that the value could be different on each switch.

You are helping the developer understand how to develop an NAE script for this use case.

You are helping a customer define an NAE script for AOS-CX switches. The script will monitor statistics from a RADIUS server defined on the switch. You want to future proof the script by enabling admins to select a different hostname or IP address for the monitored RADIUS server when they create an agent from the script.

What should you recommend?

Refer to the scenario.

# Introduction to the customer

You are helping a company add Aruba ClearPass to their network, which uses Aruba network infrastructure devices.

The company currently has a Windows domain and Windows CA. The Window CA issues certificates to domain computers, domain users, and servers such as domain controllers. An example of a certificate issued by the Windows CA is shown here.

The company is in the process of adding Microsoft Endpoint Manager (Intune) to manage its mobile clients. The customer is maintaining the on-prem AD for now and uses Azure AD Connect to sync with Azure AD.

# Requirements for issuing certificates to mobile clients

The company wants to use ClearPass Onboard to deploy certificates automatically to mobile clients enrolled in Intune. During this process, Onboard should communicate with Azure AD to validate the clients. High availability should also be provided for this scenario; in other words, clients should be able to get certificates from Subscriber 2 if Subscriber 1 is down.

The Intune admins intend to create certificate profiles that include a UPN SAN with the UPN of the user who enrolled the device.

# Requirements for authenticating clients

The customer requires all types of clients to connect and authenticate on the same corporate SSID.

The company wants CPPM to use these authentication methods:

EAP-TLS to authenticate users on mobile clients registered in Intune

TEAR, with EAP-TLS as the inner method to authenticate Windows domain computers and the users on them

To succeed, EAP-TLS (standalone or as a TEAP method) clients must meet these requirements:

Their certificate is valid and is not revoked, as validated by OCSP

The client's username matches an account in AD

# Requirements for assigning clients to roles

After authentication, the customer wants the CPPM to assign clients to ClearPass roles based on the following rules:

Clients with certificates issued by Onboard are assigned the "mobile-onboarded" role

Clients that have passed TEAP Method 1 are assigned the "domain-computer" role

Clients in the AD group "Medical" are assigned the "medical-staff" role

Clients in the AD group "Reception" are assigned to the "reception-staff" role

The customer requires CPPM to assign authenticated clients to AOS firewall roles as follows:

Assign medical staff on mobile-onboarded clients to the "medical-mobile" firewall role

Assign other mobile-onboarded clients to the "mobile-other" firewall role

Assign medical staff on domain computers to the "medical-domain" firewall role

All reception staff on domain computers to the "reception-domain" firewall role

All domain computers with no valid user logged in to the "computer-only" firewall role

Deny other clients access

# Other requirements

Communications between ClearPass servers and on-prem AD domain controllers must be encrypted.

# Network topology

For the network infrastructure, this customer has Aruba APs and Aruba gateways, which are managed by Central. APs use tunneled WLANs, which tunnel traffic to the gateway cluster. The customer also has AOS-CX switches that are not managed by Central at this point.

# ClearPass cluster IP addressing and hostnames

A customer's ClearPass cluster has these IP addresses:

Publisher = 10.47.47.5

Subscriber 1 = 10.47.47.6

Subscriber 2 = 10.47.47.7

Virtual IP with Subscriber 1 and Subscriber 2 = 10.47.47.8

The customer's DNS server has these entries

cp.acnsxtest.com = 10.47.47.5

cps1.acnsxtest.com = 10.47.47.6

cps2.acnsxtest.com = 10.47.47.7

radius.acnsxtest.com = 10.47.47.8

onboard.acnsxtest.com = 10.47.47.8

The customer needs a secure way for users to enroll their new wireless clients in Intune. You are recommending a new WLAN that will provide the users with limited access for the enrollment.

You have set up captive portal for clients on this WLAN to a web page with instructions for enrolling devices. You will need to add several hostnames to the captive portal allowlist manually.

What is one of those hostnames?

Refer to the scenario.

A customer requires these rights for clients in the "medical-mobile" AOS firewall role on Aruba Mobility Controllers (MCs):

Permitted to receive IP addresses with DHCP

Permitted access to DNS services from 10.8.9.7 and no other server

Permitted access to all subnets in the 10.1.0.0/16 range except denied access to 10.1.12.0/22

Denied access to other 10.0.0.0/8 subnets

Permitted access to the Internet

Denied access to the WLAN for a period of time if they send any SSH traffic

Denied access to the WLAN for a period of time if they send any Telnet traffic

Denied access to all high-risk websites

External devices should not be permitted to initiate sessions with "medical-mobile" clients, only send return traffic.

The exhibits below show the configuration for the role.

There are multiple issues with the configuration.

What is one of the changes that you must make to the policies to meet the scenario requirements?

(In the options, rules in a policy are referenced from top to bottom. For example, "medical-mobile" rule 1 is "ipv4 any any svc-dhcp permit," and rule 8 is "ipv4 any any any permit'.)

You are designing an Aruba ClearPass Policy Manager (CPPM) solution for a customer. You learn that the customer has a Palo Alto firewall that filters traffic between clients in the campus and the data center.

Which integration can you suggest?

Refer to the scenario.

An organization wants the AOS-CX switch to trigger an alert if its RADIUS server (cp.acnsxtest.local) rejects an unusual number of client authentication requests per hour. After some discussions with other Aruba admins, you are still not sure how many rejections are usual or unusual. You expect that the value could be different on each switch.

You are helping the developer understand how to develop an NAE script for this use case.

The developer explains that they plan to define the rule with logic like this:

monitor > value

However, the developer asks you what value to include.

What should you recommend?

Refer to the scenario.

A customer has an AOS10 architecture that is managed by Aruba Central. Aruba infrastructure devices authenticate clients to an Aruba ClearPass cluster.

In Aruba Central, you are examining network traffic flows on a wireless IoT device that is categorized as "Raspberry Pi" clients. You see SSH traffic. You then check several more wireless IoT clients and see that they are sending SSH also.

You want an easy way to communicate the information that an IoT client has used SSH to Aruba ClearPass Policy Manager (CPPM).

What step should you take?

You are reviewing an endpoint entry in ClearPass Policy Manager (CPPM) Endpoints Repository.

What is a good sign that someone has been trying to gain unauthorized access to the network?