HPE7-A08 HPE Aruba Networking Certified Professional – Switching Questions and Answers

To monitor BGP neighbor state changes and automatically create a helpdesk ticket, the NAE (Network Analytics Engine) action to use is a REST API call. This allows integration with external ticketing or automation systems, enabling automated ticket creation when a monitored event occurs.

Executing shell commands, sending emails, or generating logs are limited to internal actions and do not integrate as seamlessly with helpdesk systems.

REST API calls allow custom integration and automation.

The LACP state event Actor state: ALFNCD, Partner state: ASFNCD indicates that the LACP negotiation between the local (actor) and peer (partner) is successful with all flags matching and no errors.

ALFNCD and ASFNCD are standard LACP states indicating Active, Long timeout, Aggregation capable, Not synchronized, Collecting, and Distributing flags set as expected.

Also, the log shows the LACP rate is set to slow, which is the default.

Thus, the output shows the LAG 253 has a matching LACP configuration with its peer.

The multicast group address 239.0.0.1 falls within the administratively scoped multicast addresses but overlaps with the Link-Local Multicast address scope (224.0.0.0/24), which is reserved for protocol control traffic and should not be used for application multicast groups. Using an address that overlaps with the Link-Local scope can cause multicast routing and forwarding issues, leading to video streaming clients not receiving the stream.

IGMP snooping version or enabling IGMP without multicast traffic do not cause this issue.

PIM-SM discovery addresses are different multicast addresses.

When troubleshooting downloadable user roles (DUR) between Aruba CX switches and ClearPass, it is crucial to verify the Trust Anchor profile on the switch. The Trust Anchor profile contains the certificates and keys that allow secure communication and authentication with ClearPass, ensuring the switch can validate the RADIUS server and downloaded user role information.

SNMP community string (Option A) is unrelated to DUR.

User-role configuration (Option B) is important but verifying trust anchor ensures secure role downloads.

HTTPS client certificate (Option C) is not typically part of DUR authentication.

Therefore, the Trust Anchor profile must be verified.

The LACP fallback command in Aruba VSX configurations allows the system to continue forwarding traffic even if LACP negotiation fails or is not established. This is useful when provisioning a gateway or link that does not support LACP, ensuring that the port remains operational in a static manner.

It is not specifically for backward compatibility with LACP v1.

It does not relate to operation with a single partner interface.

It also is not about active/passive LACP modes per se.

Therefore, LACP fallback is configured to support provisioning a gateway without LACP.

To prevent rogue DHCP servers in a VLAN, DHCP snooping authorized-server commands are used to specify trusted DHCP servers allowed to respond.

Option A (dhcpv4-snooping trust 10.100.100.10) configures a trusted port, but it is not VLAN specific and not precise enough for this purpose.

Enabling DHCP snooping globally and on VLAN or interface (Options C and D) are prerequisites but do not prevent rogue servers unless authorized servers are defined.

Option B correctly enables an authorized DHCP server IP on VLAN 30, blocking unauthorized DHCP responses.

When line card LEDs do not light up, and the cards are newly installed, the best troubleshooting methodology is Divide and conquer by swapping the line cards. This method isolates the problem by testing hardware in different slots or known working units.

Spot the difference involves comparing configurations, which does not directly isolate hardware failure.

Follow the path is more suited for connectivity issues.

Replace configuration relates to software or config problems.

Hardware issues are best isolated by physically swapping components.

Comprehensive Detailed Explanation:

When a recent configuration change causes a spike in CPU utilization that negatively impacts users, the fastest way to restore normal operation is to revert the change. This rollback immediately removes the offending configuration, potentially stabilizing the CPU and restoring service.

Rebooting the switch (Option A) is disruptive and takes more time.

Disabling debug logging (Option C) may help if debug is causing high CPU, but it doesn't undo config changes.

Pausing NAE monitoring (Option D) only suspends monitoring and doesn’t address the root cause.

Hence, reverting the recent config change is the best immediate action.

The question concerns an OSPF configuration where the interface does not come up as expected.

Common reasons for no OSPF adjacency or interface participation include:

Interfaces being passive (no adjacency formed)

Mismatched OSPF process IDs

Missing loopback interfaces (for router ID)

Layer-3 interfaces not associated with VRFs when VRFs are configured

Option D (a Layer-3 interface has not been associated with a VRF) is the root cause because in Aruba CX switches, when VRF is configured, all Layer-3 interfaces that participate in OSPF must be associated with the correct VRF instance to establish adjacency and participate correctly.

If an interface is not part of the VRF configured for OSPF, it will not appear in the OSPF interface list or form neighbors.

During a VSX firmware upgrade, the vsx-syned process stops synchronization while the switches have mismatched software versions. Synchronization resumes once both switches run the same software.

VSX synchronization cannot continue while versions mismatch (contrary to options B and D).

Compatibility mode is not required before rebooting secondary switch (Option D incorrect).

This behavior ensures consistency and avoids split-brain during upgrades.

In VSX architecture, the Inter-Switch Link (ISL) is implemented as a Link Aggregation Group (LAG). To ensure proper forwarding and VLAN consistency, the ISL LAG must allow all configured VLANs. This allows VSX synchronization and data forwarding across all VLANs that span the two switches.

ISL traffic is not specifically tagged with EF QoS markings by default.

ISL traffic is not encapsulated in GRE tunnels.

The ISL LAG does not automatically include all VLANs; VLANs must be allowed on the LAG explicitly.

Hence, the LAG must be configured to allow all VLANs.

The question relates to configuring port 1/1/44 on an Aruba CX 8325 switch to connect to a 2930F switch (Aruba 2930F series). The key factor is interoperability between these two devices, especially regarding link aggregation and port channel settings.

The Aruba 2930F typically uses static or LACP link aggregation with standard settings. To connect an Aruba CX 8325 port to a 2930F port, the CX configuration must align with the 2930F settings, particularly regarding:

Enabling LACP (Link Aggregation Control Protocol) on the port.

Correct VLAN tagging or trunk mode.

Matching speed and duplex settings.

From the options given, answer A corresponds to enabling LACP with appropriate trunk configuration that matches the 2930F. The other options either have mismatches in aggregation or trunking mode or missing LACP.

The event message:

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2024-04-04T08:35:38.312254+00:00 ICX-Core-1 hpe-vaxd[2167]: Event[701|LOG_INFO|AMM1/1|VSX2 state local up, remote down]

indicates that the local VSX member is up, but the remote VSX member is down. In a VSX pair, both switches must be operational for full redundancy and synchronization.

This log means the secondary VSX switch (remote) is down or unreachable, causing loss of synchronization and possibly traffic failover issues.

Option B (keepalive detection) is related but the event specifically shows the state of the remote switch being down.

Options C and D refer to LAG or interface state, which are not what this log entry describes.

When adding a switch with an existing configuration into a group in Aruba Central, the group requires devices to have factory default configurations to allow Central to apply the group config correctly.

If the switch has an existing configuration, synchronization and auto-commit may fail because of configuration conflicts.

Option A: Pending authorization is unrelated to config synchronization.

Option C: Auto-commit can be disabled but does not block syncing existing config.

Option D: VSX support limitations are irrelevant here.

Therefore, the likely cause is that only switches with factory default config can be added to a group with existing config.

The Local Priority (LP) applied to an incoming packet marked with DSCP 46 and CoS 7 depends on the configured QoS mapping.

DSCP 46 corresponds to Expedited Forwarding (EF), which is typically mapped to the highest priority.

CoS 7 also indicates high priority.

According to the QoS policy shown, the LP assigned is 1, indicating the highest priority level.

When establishing eBGP peering between devices that are not directly connected, the TTL (Time To Live) value of the BGP packets must be increased to allow them to traverse multiple hops. This is achieved by configuring ebgp-multihop, which increases the TTL beyond the default value of 1.

next-hop-self changes the BGP next-hop attribute but is not required for multihop eBGP.

route-reflector is a BGP design feature unrelated to multihop.

address-family ipv4 external is not a standard command on Aruba CX switches.

Therefore, to successfully peer eBGP sessions across multiple hops, ebgp-multihop must be configured.

To keep the BGP routing table size manageable and below a specified threshold, the customer should consider enforcing routing policies with aggregation. Route aggregation reduces the number of individual routes advertised and stored by combining multiple routes into a summarized one.

Setting route metrics equal or advertising only a primary path does not reduce the number of routes as effectively.

Importing only the default route (0.0.0.0/0) is impractical for normal operations.

Thus, route aggregation is the best practice for controlling routing table size in merged BGP environments.

Valid Network Analytics Engine (NAE) agent actions include:

Running CLI commands (Option A), allowing automated command execution for remediation or data collection.

Generating local system logs (Option C) for event tracking and audit purposes.

Other options:

Generating SNMP traps (B) and starting/stopping packet captures (D) are not typical NAE actions.

Creating a new TAC case (E) is an external process, not an automated NAE action.

In the exhibit, the CX8325 switch ports 1/1/47 and 1/1/48 are connected in a VSX setup. According to Aruba VSX best practices, ports on the CX8325 switch that serve as ISL or VSX interconnects should use SFP28 optics for 25Gbps links. If SFP56 optics are used, it would be incorrect because CX8325 ports are designed to support SFP28 modules for these speeds.

CX6300 ports use SFP56 or QSFP28 depending on model and link speed.

CX8300 series ports designed for QSFP28 for higher speeds.

Hence, the best practice is to use SFP28 on CX8325 for the interconnect links.