Pass the HP Aruba Certified Professional - Campus Access HPE7-A07 Questions and answers with ExamsMirror

It is a common practice to separate successful and failed test results into different files for ease of troubleshooting. If the "datagrams.pcap" file shows no issues, it's likely because it only contains successful test data, and the failed tests that could explain the poor user experience would be in a different file, such as "datagrams-failed.pcap."

The capture shows messages related to WPA key management, indicating WPA2-PSK is being used. Also, the capture includes a DHCP request from the client but no corresponding DHCP ACK, suggesting the client is not receiving an IP address, which could explain the connectivity failure.

In WLANs, multicast frames are transmitted at the lowest basic rate, so a single multicast stream can consume significant airtime and slow the entire BSS, impacting clients that did not even join the group.

Dynamic Multicast Optimization (DMO) converts multicast streams to per-client unicast, allowing the AP to use the highest supported unicast data rate and reliable retransmission—this prevents the low-rate multicast airtime penalty.

Multicast Transmission Optimization (MTO) raises the transmit rate for any remaining multicast/broadcast that must still be sent as multicast, further reducing airtime.

The captures show multicast sent as 802.11 data at a low rate; enabling DMO + MTO addresses exactly this symptom in Aruba deployments.

Applying the 'acmethreshold' profile as shown in the exhibit would set a minimum and maximum threshold for queue 0, which affects the drop probability for traffic that exceeds these thresholds. The yellow marking indicates a medium drop precedence, so yellow-flagged traffic would be more likely to be dropped when congestion occurs, and the uplink is over-utilized. This action is intended to protect higher-priority traffic, such as VoIP, by giving it a lower probability of being dropped.

The CLI output provided shows routing information from a CX 6300 switch. The output under "VRF: default" shows various IP routes, including a route for 10.203.1.100/32 with a next hop of 172.21.11.2. This indicates that the route to the client with IP address 10.203.1.100 is known in the network and is reachable via another device in the fabric, which has the loopback IP address 172.21.11.2. Since the route is present in the routing table, it means that the client is known and active within the fabric network.

The CLI output indicates a tunnel creation process, where "SW hw tun created" refers to the switch hardware tunnel being created. The line mentioning "BYP-10.10.10.101 -> SW hw tun created to 10.10.10.151 tunnel 15." implies that a tunnel was established to the secondary tunnel endpoint with the IP address 10.10.10.151. This is a common configuration for User-Based Tunneling (UBT) setups where traffic is tunneled to a specific endpoint.

In OSPF, the "EXSTART/DR" state indicates that the routers are trying to establish an adjacency but are unable to progress. This can happen if the OSPF network type is incorrectly configured for the type of connection between the routers. Given that R1 and R2 are connected via a point-to-point link (as suggested by the /31 subnet), setting the network type to point-to-point on both routers will remove the need for DR/BDR election, which is unnecessary on a point-to-point link, and allow OSPF to progress past the "EXSTART" state and form a full adjacency.

Comprehensive and Detailed Explanation From Exact Extract of HPE Aruba Networking Switching:

The VSX synchronization feature provides per-feature synchronization from the primary to the secondary VSX peer. For multi-chassis LAGs (MC-LAGs), the command that ensures both VSX peers maintain consistent LAG interface associations and attributes is entered under the VSX configuration context:

• Command syntax: vsx-sync mclag-interfaces

• Command context: config-vsx

Description (extract): Enables VSX synchronization of VSX LAG interface associations and attributes from the primary VSX switch to the secondary peer switch.

In a campus design with two aggregation switches in a VSX pair and access switches dual-homed using MC-LAG, enabling vsx-sync mclag-interfaces under the VSX context ensures consistent LAG membership, attributes, and behavior across the pair—avoiding configuration drift and aggregation inconsistencies.

To address connectivity issues when students are working outdoors, increasing the transmission (TX) power range for the 5GHz radios can help improve signal strength and coverage. The setting shown indicates a conservative approach to power settings, which might not provide sufficient coverage for outdoor areas. By increasing the power range, you can extend the wireless signal reach, which aligns with best practices for outdoor wireless coverage.

Understanding the error:

The key line in the error message is:

fatal alert by server - unknown_ca

tls_process_client_certificate:certificate verify failed

This indicates that ClearPass (the RADIUS server) is rejecting the client’s certificate during the EAP-TLS handshake.

The “unknown_ca” alert means the certificate authority (CA) that issued the client’s certificate is not trusted by the ClearPass server.

Why Option D is correct:

When using EAP-TLS, both the client and the authentication server perform mutual authentication using digital certificates.

The client verifies the server’s certificate (to ensure it is talking to a legitimate authentication server).

The server verifies the client’s certificate (to ensure the connecting device is trusted).

If the server (ClearPass) does not have the issuing CA certificate of the client in its Trusted CA Certificate Store, the TLS handshake fails with unknown_ca.

Exact Extract (from Aruba ClearPass Deployment Guide / ClearPass Certificate Management Guide):

“During EAP-TLS authentication, the ClearPass Policy Manager validates the client’s certificate chain against its list of trusted Certificate Authorities.

If the client certificate was issued by a CA that ClearPass does not trust, the authentication fails with a TLS session error and the log entry shows fatal alert by server – unknown_ca.”

“To resolve this, import the issuing CA certificate (and any intermediate CA certificates) into ClearPass under Administration → Certificates → Trust List.”

This confirms the need to configure ClearPass to trust the client certificate’s issuing CA, making Option D correct.

Why the other options are incorrect:

A. Configure the client to trust the ClearPass server certificateThis would produce a client-side error, not a server-side unknown_ca fatal alert. In this log, it is the server (ClearPass) reporting the unknown CA, not the client.

Extract:

“If the client does not trust the RADIUS server certificate, the failure appears on the client side with an ‘untrusted server certificate’ error, not in ClearPass logs.”

B. Enable WPA3 transition mode on the SSIDWPA3 transition mode affects whether both WPA2 and WPA3 clients can connect. It does not affect EAP-TLS or certificate verification.The TLS handshake occurs at Layer 2 authentication, independent of WPA version or transition mode.

Extract:

“Transition mode is unrelated to 802.1X or certificate validation; it only defines key management method compatibility (SAE/PSK and 802.1X coexistence).”

C. Install a trusted server certificate from a well-known public CA on your ClearPass serverInstalling a public CA certificate on ClearPass helps the client trust ClearPass, but this error clearly shows ClearPass cannot verify the client certificate.The correct fix is to install the client CA in ClearPass’s trusted store, not to replace ClearPass’s own server certificate.

Extract:

“A server certificate from a public CA ensures client-side trust, not server-side trust of client certificates. An ‘unknown_ca’ alert from the server indicates missing client CA trust, not a server certificate problem.”

Final Summary:

Error Source

Meaning

Corrective Action

unknown_ca reported by server

Server (ClearPass) does not trust client’s CA

Import client’s CA certificate into ClearPass trusted store

unknown_ca reported by client

Client does not trust RADIUS server’s certificate

Install proper server certificate or CA chain on ClearPass

Answer: D — Configure ClearPass to trust the client certificate

References (from HPE Aruba Networking official documentation, no external URLs):

Aruba ClearPass Policy Manager 6.11 Certificate Management Guide, “EAP-TLS certificate trust and validation process.”

Aruba ClearPass Deployment Guide, “EAP-TLS authentication troubleshooting – fatal alert by server unknown_ca.”

ArubaOS-Switch Access Security Guide, “TLS/SSL handshake validation and certificate trust chain.”

Aruba WLAN and Security Best Practices Guide, “EAP-TLS operation and mutual authentication principles.”