800-150 Cisco Supporting Cisco Devices for Field Technicians (FLDTEC) Free Practice Exam Questions (2025 Updated)

Step 1 → Performs power-on self-test (POST)

Step 2 → Loads and runs bootstrap code (firmware)

Step 3 → Finds and loads the Cisco IOS software

Step 4 → Finds and loads the configuration

Step 5 → Runs the configured Cisco IOS software

This startup process is thoroughly described in theFLDTECcourse and alignswith Cisco's standard IOS boot process:

POST (Power-On Self-Test):Verifies hardware functionality including memory and interfaces. This occurs immediately upon powering the device.

Bootstrap Code Execution:Bootstrap is a small program in ROM that initiates the boot process.

Cisco IOS Loading:Bootstrap locates and loads the IOS from flash memory or another source (e.g., TFTP).

Configuration Loading:The router then loads the startup-config from NVRAM (if available).

IOS Execution:Once the configuration is loaded, the device enters operational mode and executes the IOS with the loaded config.

This sequence is vital for field technicians to understand for troubleshooting boot failures or performing device recoveries.

In theFLDTEC course, underSafety and ESD Procedures, Cisco outlines the following safety workflow before working on any network hardware:

Locate Emergency Power-Off Switch: Identifying how to cut power quickly is essential in case of an electrical fault or emergency.

Disconnect Power: Always ensure the power source is turned off and disconnected before handling any components.

Verify with Multimeter: Use a multimeter to confirm that no voltage is present before proceeding.

Connect ESD Strap: Once confirmed safe, attach your ESD strap to a grounded point to prevent electrostatic damage to sensitive components.

Following this process is critical not only forpersonal safetybut also forequipment protection, especially duringhardware installation, maintenance, or RMA replacements.

Theshow flash:command is used todisplay the contents of the device's flash memory, which is where the Cisco IOS image is typically stored. By issuing this command, a technician can verify available space and determine whether there is enough capacity to accommodate a new IOS image before initiating an upgrade or image replacement process.

This command provides a detailed listing of files, their sizes, and the total and available memory space within the flash file system.

show file-systemlists all available file systems but doesn’t detail their content.

show memoryshows runtime memory usage (RAM), not flash memory.

show storageis not a standard IOS command.

During the password recovery process on Cisco devices, ROMMON (ROM Monitor) mode is utilized to perform specific actions that facilitate the recovery. Two critical actions typically performed in ROMMON mode are:​

Change the Configuration Register:The configuration register is modified to instruct the device to ignore the startup configuration during the next boot. This is commonly achieved by setting the configuration register to0x2142. This action prevents the device from loading the saved configuration, allowing access without requiring the existing passwords.​

Reboot the Device:After changing the configuration register, the device is rebooted to apply the new settings. This reboot enables the device to bypass the startup configuration, facilitating the password recovery process.​

These steps are essential in the password recovery procedure, allowing administrators to regain access to the device without erasing the existing configuration.​

During the boot process of Cisco devices runningNX-OS, pressingCtrl-Cat the right time will interrupt the boot sequence and bring the system to theboot loader or ROMmon mode(commonly referred to as the boot prompt).

This allows a technician to perform low-level operations such as recovering passwords, specifying an alternate boot image, or performing diagnostics.

Other options (Ctrl-X, Ctrl-Z, Ctrl-1) are not used for interrupting the boot process in Cisco NX-OS platforms.

Theshow interface statuscommand offers a succinct overview of switch port characteristics, including:​

Port ID

VLAN assignment

Duplex mode

Speed

Media type​

This command is particularly useful for quickly assessing theoperational status and configuration of switch ports, aiding in troubleshooting and verification tasks.​

In contrast:​

show cdp neighborsdisplays information about directly connected Cisco devices.

show controllersprovides low-level hardware information.

show ip interface briefoffers a summary of IP-related interface information.​

These components are part of theCisco Collaboration System Architecture (CSA), and are reviewed in theFLDTEC trainingunderCisco Equipment and Collaboration Basics:

Call Control: Managed by services likeCisco Unified Communications Manager (CUCM), it routes and connects calls.

Collaboration Applications: Provide added value services such asvoicemail (Unity),messaging (IM&P), presence, and more.

Edge Devices: IncludeCisco ExpresswayandCUBE(Cisco Unified Border Element), offering secure access and traversal for mobile/remote endpoints.

Conferencing: Powered by platforms likeCisco Meeting ServerorWebex, enabling multi-party conferencing.

Endpoints: Include bothhardware (IP phones, video units)andsoftware (Webex app)that users interact with directly.

TheSpine-and-Leafarchitecture is the preferredpod-based deployment modelin modern data centers because of itshigh scalability and flexibility. In this topology:

Leaf switchesconnect to servers and act as the access layer.

Spine switchesfunction as the core layer, interconnecting all leaf switches.

This non-blocking, highly redundant model supportspredictable latency, easy horizontal scaling, and load balancing, making it ideal for cloud-scale and virtualized environments.

Top of Rack (ToR)andEnd of Row (EoR)are physical cabling layouts that do not inherently provide the same level of architectural scalability.

Fabric Extender modelsextend switch ports but depend on upstream switches for intelligence, limiting flexibility.

TheWireless LAN Controller (WLC)plays a central role in Cisco’s Unified Wireless Network solution by providing centralized management, configuration, and monitoring for multiple access points (APs). It allows for streamlined policy enforcement, seamless mobility, load balancing, and security management across wireless networks.

While WLCs facilitate wireless connectivity indirectly, their main role is tocentrally manage and controlaccess points — not to function as Layer 3 routers or format data frames.

Acrossover UTP (Unshielded Twisted Pair) cableis used to connect two similar devices directly. This includes:​

Switch to switch

Router to router

PC to PC​

The crossover cable reverses the transmit and receive pairs, allowing for proper communication between like devices without the need for an intermediary device.​

Conversely, astraight-through cableis used to connect dissimilar devices, such as:​

PC to switch

Router to switch

PC to router​

This cable maintains the same wiring on both ends, suitable for connecting different types of devices.​

Therefore, when connecting electrically like devices, a crossover cable is appropriate.​

In a Class B network, the default subnet mask is 255.255.0.0, which allocates:​

16 bits for the network portion

16 bits for the host portion​

When the subnet mask is changed to255.255.255.0, it becomes:​

24 bits for the network portion

8 bits for the host portion​

This indicates that8 bitshave been borrowed from the host portion to create additional subnets. Borrowing bits allows for the division of the original network into smaller sub-networks, enhancing organization and security within the network.​

For standalone Cisco Secure Firewall deployments, theCisco Secure Firewall Device Manager (FDM)is the most appropriate management option. FDM is a browser-based, on-box management tool that allows administrators to configure and manage a single firewall device without the need for external management infrastructure. It provides an intuitive interface for basic configurations, policy management, and monitoring.​

In contrast:​

Cisco Secure Firewall Management Center (FMC)is designed for centralized management of multiple firewall devices.

Cisco Defense Orchestrator (CDO)is a cloud-based solution for managing security policies across various devices.

Cisco Security Manageris an older platform primarily used for managing ASA devices.​

A → Power supply modules

B → Fan tray assembly

C → Line card slots 1 and 2

D → Supervisor modules

E → Line card slots 5, 6, and 7

The power supply units (A) are at the top, the fan tray (B) is a vertical module on the left, line cards (C and E) span multiple slots horizontally, and supervisor modules (D) are typically placed centrally for control functions.

In theFLDTEC courseunderCisco Modular Hardware Overview, the Cisco Catalyst 9400 series is broken down into clearly defined FRU zones:

Power Supply Modules (A):Located at thetop of the chassis, these provide redundant, hot-swappable power to the switch.

Fan Tray Assembly (B):Mounted vertically on the left, this ensures proper cooling and airflow throughout the chassis.

Line Card Slots 1 and 2 (C):Located in the upper section for network expansion.

Supervisor Modules (D):Positioned centrally, they handle control plane operations, management, and switching logic.

Line Card Slots 5, 6, and 7 (E):Lower slots for high-density port expansion.

Correct FRU identification ensures successful maintenance, upgrades, and hardware replacement during field operations.

TheCisco Integrated Management Controller (CIMC)is the embedded management solution designed specifically forstandalone Cisco UCS C-Series rack servers and E-Series servers. It allows administrators to perform out-of-band management functions such as BIOS configuration, firmware updates, remote console access, and power control.

Cisco UCS Manageris used for managing UCS blade chassis environments.

Cisco UCS Centralis intended for centralized management across multiple UCS domains.

Cisco Intersightis a cloud-based management platform that can extend CIMC functionality but is not the embedded, standalone option.

In a local area network (LAN), the primary function of aswitch is to operate at Layer 2 (Data Link Layer) of the OSI model. Switches use MAC addresses to forward frames to the appropriate destination ports. This targeted forwarding mechanism divides the network into separate collision domains for each switch port. By isolating collision domains, switches significantly reduce the chance of collisions, enhancing the performance and efficiency of the network.

Unlike hubs, which forward all traffic to all ports (thus creating a single collision domain), switches intelligently forward only the necessary traffic to the correct port. This capability allows multiple simultaneous conversations on different switch ports without interference.

Routers, which operate at Layer 3 (Network Layer), are used to route packets between different networks, not within the same LAN. Wireless connectivity is provided by wireless access points (WAPs), not switches. Encryption is typically handled by security protocols or devices such as firewalls and not by switches directly.

Cisco Nexus switchesare specifically designed for deployment indata centers, where they providehigh-performance, low-latency switchingto support modern workloads, virtualization, and cloud computing environments.

Nexus switches operate usingNX-OS, a purpose-built operating system optimized for data center needs. These switches support technologies like virtual port channels (vPC), FabricPath, and Application Centric Infrastructure (ACI), which are essential for scalable and highly available data center networks.

They are not typically used in branch offices, as wireless access points, or as edge routers.

TheCisco Catalyst 9000 Seriesis engineered to address the evolving needs of modern enterprise networks by integrating the functionalities of both the core and distribution layers into a unified, converged architecture. This series offers advanced capabilities such as high-speed data forwarding, enhanced security features, and support for automation and programmability, making it suitable for scalable and efficient network designs.​

The Catalyst 9000 Series includes models like the Catalyst 9500 and 9600, which are optimized for core and distribution roles, providing high throughput and reliability. These switches support advanced features like Software-Defined Access (SD-Access) and are designed to meet the demands of cloud-scale and security-focused environments.​

In contrast, theMeraki MS400 Series(Option A) is tailored for cloud-managed aggregation and lacks the comprehensive feature set required for core functionalities. TheCatalyst 6500 E-Series(Option B), while historically significant, is considered a legacy platform and may not support the latest advancements in network convergence. TheCatalyst 1300 Series(Option C) is designed for small to medium-sized businesses and is not intended for core or distribution layer deployments.​

On Cisco Catalyst 8000 Series Edge platforms, removing the chassis cover provides access to internal components such asDIMMs (Dual In-line Memory Modules)andSSDs (Solid-State Drives). These components are located internally and require the removal of the chassis cover for maintenance or replacement.​

DIMMsare used for system memory and are essential for the router's operation.

SSDsprovide storage for system software and configurations.​

Other components likeNetwork Interface Modules (NIMs)andtransceiversare typically accessible externally and do not require chassis cover removal.​

In the providedCisco UCS architecture diagram, the infrastructure consists of:

Two Fabric Interconnects (A and B), each connecting to:

Ethernet (LAN)

Fibre Channel (FC)

FCoE (Fibre Channel over Ethernet)

Both Fabric Interconnects are independently connected to bothCisco UCS Chassis 1 and 2through I/O Modules (IOMs).

This is theclassic active-active UCSdesign, providingfull path redundancyfor all traffic types:

LAN uplinksare handled separately by Fabric Interconnect B.

SAN trafficis distributed throughFC uplinksandFCoE uplinksvia Fabric Interconnects A and B.

Each server in the chassis canfail over its traffic to the alternate fabric if one interconnect fails.

This architecture guaranteesno single point of failure, which is essential inmission-critical environmentslike data centers and enterprise server farms.