HPE7-A08 Sample Questions Answers

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.

IGMP (Internet Group Management Protocol) supports several message types: Join, Leave, Query, and Report messages to manage multicast group membership.

Join messages indicate a host wants to join a multicast group.

Leave messages indicate a host is leaving a multicast group.

Query messages are sent by routers to discover group members.

Report messages are sent by hosts to indicate membership.

Therefore, the full set of IGMP message types supported includes Join, Leave, Query, and Report.

Options with only Leave and Report or only Join and Query are incomplete.

LACP (Link Aggregation Control Protocol) modes can be active or passive. When two switches are both configured in passive mode, no LACP packets are initiated, causing the link aggregation to fail or go into a block state.

Changing one side from passive to active causes that switch to initiate LACP negotiation, resolving the block state.

Changing to static mode disables LACP negotiation, which is not recommended unless both sides are static.

Changing timeout does not solve LACP block issues caused by mode mismatches.

Therefore, changing one switch’s LACP mode from passive to active is necessary to resolve the block.

Using the command copy checkpoint 20240722 running-config exemplifies the Replace configuration troubleshooting methodology. This involves replacing the current running configuration with a known good checkpoint to restore proper operation.

Divide and conquer isolates faults by segment.

Top-down/Bottom-up analyzes layer by layer.

Spot the difference compares configurations.

Replacing the config is a straightforward rollback approach.

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:

VLAN 1 is often configured as the native VLAN on interfaces to support Zero Touch Provisioning (ZTP). During ZTP, devices communicate over VLAN 1 by default to download their configuration and updates.

LLDP and UBT are unrelated to native VLAN configuration for provisioning.

MSTP relates to spanning tree but does not dictate native VLAN usage.

Thus, VLAN 1 as native VLAN facilitates ZTP processes.

In a hotel environment where a single subnet is used for wired guests, but guest devices in a conference room need to communicate with each other (and with the default gateway), while remaining isolated from other guests elsewhere, Community VLANs are appropriate.

Community VLANs allow hosts within the same VLAN community to communicate with each other and the default gateway but are isolated from hosts in other communities.

Isolated VLANs block communication between ports and only allow communication to the gateway.

Therefore, assigning conference room guests to a community VLAN and the gateway to a primary VLAN allows the desired communication model.

To receive a monthly report tracking available licenses and their expiration dates in Aruba Central, the Infra Inventory report should be scheduled. It provides detailed information about device inventories, including licenses and expiration.

Switch Capacity Planning focuses on resource utilization.

Resource Utilization monitors system performance.

Network report focuses on topology and health.

If both switches are configured with default spanning-tree priorities and both appear as primary root bridges, to have a single spanning tree domain, matching MST configuration (Multiple Spanning Tree) must be created on Core-2 to align with Core-1.

Setting priority to 1 on one switch can help but matching MST configurations is the recommended approach for multiple VLANs.

Creating MST instances on only one switch will not ensure consistency.

Matching MST configurations ensures consistent root bridge election and stable spanning tree.

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.

To upgrade an HPE Aruba Networking CX 8320 VSX cluster with minimal downtime from a remote server, the correct command is:

vsx update-software scp://172.25.101.10/image vrf mgmt

Using SCP (Secure Copy Protocol) ensures secure transfer.

Specifying vrf mgmt ensures the update uses the management VRF for connectivity.

Using TFTP is less secure and not recommended for production upgrades.

The primary keyword is not valid for the vsx update-software command.

This method allows an in-service software upgrade (ISSU) with least disruption.

To prevent the campus core from seeing the data center core as the root bridge in a spanning tree topology (which can cause suboptimal paths or loops), Root Guard should be applied on the campus-to-data center core link. Root Guard enforces root bridge placement by blocking any superior BPDU from a downstream switch, maintaining the intended root bridge location.

BPDU filter blocks BPDUs entirely, which can cause problems.

Admin edge and BPDU guard are related to edge port protection, not root placement control.

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.

When enabling ARP protection, it is best practice to wait at least a week after enabling DHCP snooping before enabling ARP protection in a live network. This allows the DHCP snooping binding table to stabilize, ensuring ARP protection has accurate IP-MAC bindings, reducing false positives.

Immediate ARP protection may cause legitimate traffic to be dropped.

Lease times and DHCP server utilization are less critical.

This staged approach minimizes disruption.

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.

The error message "Invalid input: interface" typically appears if the switch is managed by HPE Aruba Central, which restricts CLI interface configuration to prevent configuration drift. When managed externally, certain commands are disabled or locked.

Password recovery mode or authorization enabled would not cause this error.

Manager context is not a concept in Aruba CX CLI.

To capture packets on an HPE Aruba CX switch and view the output remotely in real-time, the best practice is to use a mirror session that forwards traffic to a remote device running a packet analyzer such as Wireshark. ERSPAN (Encapsulated Remote Switched Port Analyzer) allows the mirror traffic to be encapsulated in GRE and sent over an IP network to a remote monitoring station. This method ensures full packet capture with no local resource constraints and provides full visibility to the analyst.

Option B (using tcpdump on the switch) only provides summarized or limited capture locally.

Option C (mirroring to another switch port) only allows local monitoring and does not provide remote real-time viewing.

Option D (mirror to CPU and then use tshark) is less efficient and may be resource-intensive on the switch.

Therefore, configuring ERSPAN to a remote Wireshark host is the recommended and best way.

For an interface connected to an untrusted device regarding DSCP markings, the recommended configurations are:

Apply a classifier-based policy to assign a Local Priority value (Option B). This overrides or marks traffic based on predefined criteria.

Configure qos trust none (Option E) to disable trusting DSCP or CoS markings from the device, preventing manipulation of QoS.

Trusting CoS (Option A) is incorrect because the device is untrusted.

DSCP maps and Weighted Fair Queuing (Options C and D) are additional QoS features but do not specifically address untrusted markings.

To determine which sites would benefit most from upgrading from 6200 to more powerful 6300 switches in Aruba Central, the best report to run is the Switch Capacity Planning report. It analyzes resource utilization and capacity to identify bottlenecks and potential upgrade candidates.

Infra Inventory lists devices but not capacity usage.

Resource Utilization gives raw usage but not in planning context.

Network report focuses on topology and status.

Hence, Switch Capacity Planning is the most relevant report for upgrade planning.