Free HPE6-A86 practice test: 30 questions with answers

Single-mode fiber is built for long runs such as 2 km, while Category 6 copper is limited to about 100 meters per Ethernet segment. Multimode fiber is normally used for shorter building runs, and BNC coaxial cabling is not a standard switch uplink medium.

A broadcast domain is the set of devices that receive each other's Layer 2 broadcast frames, and routers or other Layer 3 boundaries end it. A collision domain is a different concept tied to shared-media contention, and the other options describe address pools or MAC learning rather than broadcast reach.

ARP resolves an IPv4 address to a MAC address on the local segment by broadcasting a request. Routers do not forward ARP broadcasts between subnets, and ARP does not populate routing tables.

A /26 prefix provides 64 addresses, and two are reserved for the network and broadcast addresses, leaving 62 usable hosts. A /27 gives only 30 usable hosts, while /25 wastes addresses and /28 is too small.

TCP uses sequence numbers, acknowledgments and retransmission, so lost segments are resent and data is reassembled in order. UDP has none of these guarantees, ICMP is a Layer 3 control protocol, and ARP is not a transport protocol.

SFTP runs inside an SSH session, so both the credentials and the file contents are encrypted. TFTP has no authentication or encryption, SNMPv2c sends community strings in clear text, and plain HTTP is unencrypted.

A dedicated management VLAN with an IP address, SSH for encrypted sessions, and Telnet disabled gives secure management. Shared Telnet, default-VLAN access without a password, and plain HTTP all expose credentials or the device to unauthorized access.

Both ends of a link carrying several VLANs must be tagged members so each frame keeps its 802.1Q VLAN ID. An untagged single-VLAN setting cannot carry VLAN 20 across the link, and port security and matching subnet masks do not carry VLAN traffic.

LACP needs both ends to run the protocol, and member ports must match in speed and duplex so the bundle can form. Different VLANs per member, a static port on one end, or unique IP addresses on member ports are not requirements.

VLAN 30 must be carried as a tagged VLAN on the trunk between the switches, or the DHCP request never reaches the server's VLAN. Lease time, default VLAN discovery and MAC matching do not decide whether the VLAN crosses between switches.

LLDP is the IEEE 802.1AB protocol that lets directly connected devices advertise identity and port details. ARP, spanning tree and SNMP traps serve different purposes.

Checking interface, VLAN and LAG status with show commands confirms the live state against the design. Rebooting verifies nothing, swapping a cable without checking configuration is guesswork, and disabling spanning tree removes loop protection.

Aruba Central is the cloud-based platform for monitoring, configuration and firmware management across many sites. A console session or local SNMP community works one device at a time, and a TFTP server only stores files.

The command-line interface gives access to the complete set of configuration commands, including features not shown in the web interface. The web interface shows only its menu options, while syslog and SNMP traps are for event reporting rather than configuration.

The REST API lets scripts read and change configuration over HTTPS, which suits scheduled automation. The web interface needs manual interaction, console access requires physical presence, and syslog only forwards event messages.

Power over Ethernet delivers power on the same cable as data, so access points and cameras need no local outlet. Stacking, fan redundancy and SFP+ uplinks do not supply power to downstream devices.

802.1X is port-based network access control, in which the switch holds the port closed until the client authenticates, typically through a RADIUS server. Mirroring, link aggregation and spanning tree do not authenticate users.

SNMP polling and the Aruba Central cloud dashboard both let staff monitor device health remotely. Editing a startup file on a laptop does not show live status, and a higher-wattage power supply is a hardware change rather than a monitoring method.

A Layer 2 loop with an unblocked redundant path makes the same MAC address appear on two ports as frames circulate. A wrong gateway, an expired lease or a mismatched printer mask would not move a MAC address between ports.

The host cannot reach a gateway outside its subnet, so it has no next hop for traffic leaving the subnet, even though local traffic works. The other options either misdescribe spanning tree and duplex behaviour or describe DHCP settings that do not affect routing.

Rising CRC errors and late collisions usually point to a duplex mismatch, where one end is full duplex and the other is half duplex. A DHCP scope, a spanning tree priority or a VLAN name does not produce these counters.

Traceroute sends probes with increasing TTL values so each router along the path reports itself, showing where traffic stops. Ping only confirms reachability, nslookup queries DNS, and a cable tester checks the physical link.

A host reaches its gateway only if it is in the same VLAN and its subnet mask places the gateway in the same subnet. SNMP community strings and NTP time zones do not affect IP reachability to the gateway.

When the two ends of a trunk disagree on the native VLAN, untagged frames from one side are placed into a different VLAN on the other side, which breaks VLAN separation. A duplicate IP address, spanning tree priority or a larger MTU would not move frames between VLANs.

Saving configurations to an off-device backup server on a schedule lets a failed switch be restored quickly. Relying on factory defaults, keeping only running memory, or storing a single copy on the same device risks losing the configuration with the hardware.

Individual accounts authenticated through a central AAA server, such as RADIUS or TACACS+, give accountability and central control. A shared account, Telnet access and open subnet logins all weaken security.

Syslog forwards device event messages to a central logging server, so events from many switches can be reviewed together. A TFTP configuration copy, static ARP entries and port security are unrelated to centralized event collection.

NTP keeps timestamps consistent so events from different devices can be correlated, and SNMPv3 adds authentication and encryption to monitoring traffic. Disabling logs or sharing an unrestricted community string reduces visibility and security.

A read-only or monitor role limits help-desk staff to viewing status and logs while blocking configuration changes. Full administrator access and shared accounts give too much access and remove accountability, and open Telnet does not limit privileges.

A recorded plan with rollback steps and a post-change verification both reduce risk and make failures easier to recover from. Peak-hour changes and skipped backups increase the impact of a mistake.