800-150 Supporting Cisco Devices for Field Technicians (FLDTEC) Questions and Answers

To apply a prewritten configuration to a new Cisco device, the console terminal must be inGlobal Configuration Mode. This mode allows administrators to enter configuration commands that affect the device's overall operation. To access Global Configuration Mode, one must first enter Privileged EXEC Mode by typingenable, and then enterconfigure terminal. Once in Global Configuration Mode, theprewritten configuration can be pasted, and the device will accept the commands accordingly.​

In enterprise networking, remote sites or branch offices connect to the central campus network using:​

WAN Links:These are dedicated communication paths that connect geographically dispersed networks. WAN links can be leased lines, MPLS circuits, or other forms of long-distance connectivity that facilitate reliable data transmission between remote sites and the main campus.​

IPsec VPN Tunnels:Internet Protocol Security (IPsec) VPNs provide secure, encrypted tunnels over the public internet, allowing remote sites to connect to the enterprise network securely. This method is cost-effective and widely used for connecting branch offices to the central network infrastructure.​

Access layer switches (Option A) and LAN core switches (Option E) are components within a local network and do not facilitate remote connectivity. Ad hoc Wi-Fi networks (Option D) are temporary and lack the security and reliability required for enterprise-level remote connections.​

Online Insertion and Removal (OIR)is a feature supported by Cisco ASR routers that allows for the insertion and removal of hardware components, such as line cards and modules, while the router is operating. Thiscapability enables maintenance and upgrades without the need to power down the system, thus minimizing network downtime.​

Key aspects of OIR include:​

Seamless Operation:OIR allows for hardware changes without interrupting the router's operation.​

Preservation of Routing Information:The router maintains all routing information and active sessions during the insertion or removal process.

Administrative Shutdown:While not mandatory, it is recommended to administratively shut down the interfaces associated with the component being removed to ensure a graceful transition.​

This feature is particularly beneficial in high-availability environments where maintaining continuous network service is critical.​

Theinstall allcommand is the standard method used to install or upgrade Cisco NX-OS software on Nexus switches. This command streamlines the installation process by automating tasks such as verifying the software image, checking for compatibility, and managing the installation of optional packages or SMUs (Software Maintenance Upgrades). It ensures a comprehensive and efficient upgrade process, minimizing the potential for errors.​Cisco

In contrast:​

copy tftp: running-configis used to copy configuration files, not software images.

install kickstartis an outdated command from earlier NX-OS versions.

boot systemsets the boot variable but does not handle the full installation process.​

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.

Within theFLDTECtraining, especially underMaintenance and RMA Procedures, there is a strong emphasis on safely transferring and adapting configurations from failed or decommissioned devices to replacement units.

The official guidance includes the following:

"When reusing a configuration from an old device, make sure to retain the necessary security elements such as username entries. This ensures the replacement device is still accessible under the correct user credentials."

Here's a breakdown of why the correct answer isB:

A. Remove all configurations under line vty 0 4:This would eliminate remote access settings, making it harder to manage the device.

B. Retain all username entries:Correct. Keeping the username entries ensures continued secure access and avoids loss of administrative control.

C. Keep all access-list commands intact:Not always required — ACLs are often tailored to interface-specific settings or environments which may differ between devices.

D. Add the enable password cisco command:Not a best practice. Default passwords (like cisco) should be avoided for security reasons, and it's not required if enable secret is already in use.

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When diagnosing network connectivity issues between a Windows PC and a Cisco device, the combination ofipconfig /allandpingcommands provides comprehensive information:​

ipconfig /all:Displays detailed IP configuration information, including IP addresses, subnet masks, default gateways, DNS servers, and MAC addresses for all network adapters. This information is crucial for verifying correct network settings.​

ping:Tests the reachability of a host on an IP network and measures the round-trip time for messages sent from the originating host to a destination computer. It's a fundamental tool for checking connectivity between devices.​

While other commands likenetstat,tracert,nslookup,arp -a, androute printprovide valuable information,ipconfig /allandpingare typically the first and most informative commands used in initial troubleshooting steps.​

These command associations are part of Cisco IOS essentials taught in FLDTEC's "Device Configuration and Verification" topic. Here's how each command functions:

show running-config

Displays the active configuration stored in RAM.

This command is used to verify the current settings on a Cisco device.

copy running-config startup-config

Saves the current running configuration to NVRAM, ensuring the configuration persists after a reboot.

This is critical after making changes to devicesettings.

copy tftp: running-config

Loads a configuration from a TFTP server and applies it to the current running configuration.

Often used during remote device setup or restoration.

copy usbflash0:backup.cfg running-config

Restores a saved configuration file from a USB drive.

Useful in field operations where physical backup media is used during maintenance.

These tasks are routine for field technicians performing configuration backups, restorations, and diagnostics in Cisco environments.

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.

Backing up the configuration of a network device before replacement is a critical step to ensure business continuity and minimize downtime. The primary purpose of this backup is torestore the existing settings onto the new device, ensuring that it operates identically to the one being replaced.​

This process includes preserving interface configurations, routing protocols, access control lists, and other essential parameters. By restoring the backed-up configuration to the new device, network administrators can quickly reintegrate it into the network infrastructure without the need for manual reconfiguration, thereby reducing the risk of errors and service disruptions.​

Options A, B, and C do not align with the primary objective of configuration backups in the context of device replacement.​

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.

The main advantage ofCisco Intersightis itscloud-based architecture, which allows IT administrators tomanage infrastructure from any locationwithout needing to install or maintain traditional on-premises management tools.

This provides:

Centralized visibility and control over UCS servers and HyperFlex infrastructure

Remote firmware upgrades and configuration

Policy-driven automation

Unlike on-premises tools, Intersight eliminates the overhead of maintaining dedicated infrastructure for management.

In Cisco Nexus switches, when transitioning from a single supervisor module to a dual supervisor configuration, the behavior depends on the redundancy mode configured.​

Stateful Switchover (SSO):In configurations supporting SSO, the active and standby supervisors synchronize their state and configuration, allowing for seamless failover without resetting other modules.​

Stateless Switchover (Warm Standby):In certain modes, such as the ACI-mode on Cisco Nexus 9508 switches, the standby supervisor does not maintain synchronized state information with the active supervisor. In this scenario, if a switchover occurs (e.g., due to the replacement of the active supervisor), all modules in the switch are reset because the switchover is stateless.​

Therefore, when a supervisor module is replaced in a configuration that does not support stateful switchover, all modules in the switch are reset due to the stateless nature of the switchover.​

According to theCisco FLDTEC training and product documentation:

Cisco PTZ 4K Camera: Offers high-definition video capture with pan-tilt-zoom features and 4K resolution — ideal for large conference spaces.

Cisco Webex Board Pro: Interactive collaboration device that combines video conferencing, whiteboarding, and wireless content sharing.

Cisco Quad Camera: Features multiple cameras for wide-angle views, speaker tracking, and automatic framing — great for medium to large meeting rooms.

Cisco Room Navigator: A touchscreen device that provides intuitive control for room settings, scheduling, and call management.

InInstall mode, thepackages.conffile plays a crucial role in the boot process of Cisco IOS XE Software. It specifies the list of software packages to be loaded and the sequence in which they should be initialized during system startup. This file ensures that all necessary components are correctly loaded, providing a modular and flexible approach to software management.​

Contrary to the other options:​

Thepackages.conffile does not extract the bin file; it references already extracted packages.

It does not contain the entire bundled image; that's characteristic of Bundle mode.

While it resides in the flash memory, it is not a subdirectory but a configuration file.​

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.

When addressing call quality issues between IP phones, theReal-time Transport Protocol (RTP)is the primary protocol to analyze. RTP is responsible for the actual transmission of voice data during a call, and its performance directly impacts call quality.​

Key factors affecting RTP and, consequently, call quality include:​

Packet Loss:Missing packets can lead to audio gaps.

Jitter:Variations in packet arrival times can cause choppy audio.

Latency:Delays in packet delivery can result in noticeable lag.​

Analyzing RTP streams allows technicians to identify these issues and implement appropriate Quality of Service (QoS) measures to mitigate them.​

Incontrast:​

SIP (Session Initiation Protocol):Handles call setup, modification, and teardown but not the media stream.

SCCP (Skinny Client Control Protocol):A Cisco proprietary protocol for signaling, not media transport.

H.323:An older protocolsuite for multimedia communication, encompassing both signaling and media, but less commonly used in modern IP telephony.​Reference:Supporting Cisco Devices for Field Technicians (FLDTEC) – Troubleshooting Methodologie

To ensurehigh availability and fault tolerancein Cisco data center designs, two effective strategies include:

Redundant Supervisor Engines and Fabric Modules: These provide failover capabilities, so if one supervisor or fabric module fails, another can take over, maintaining network operations without interruption.

Virtual Port Channels (vPCs): vPCs allow connections to be made to two physical switches while appearing as one logical switch. This prevents loops and adds redundancy and load balancing, which is critical in high-availability environments.

Other options may enhance performance (e.g., high-density Ethernet) or extend functionality (e.g., FCIP), but do not directly contribute to fault tolerance and high availability in the same way.

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.​

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.​

Kickstart Image→ Specialized bootloader that initializes the hardware

System Image→ Contains the full NX-OS kernel and operating system

Global configuration command mode→ Provides access to the broadest range of commands that affect the device as a whole

EXEC command mode→ Allows for displaying device status and configuration information

This knowledge is covered underCisco IOS/NX-OS Software Basicsin the FLDTEC training:

Kickstart Image:Alightweight bootloader image that initializes hardware and launches the system image. It's comparable to ROMMON in traditional IOS devices.

System Image:Includes the full NX-OS operating system, services, drivers, and kernel required to run the device.

Global Configuration Mode:After entering privileged EXEC mode (enable), this mode allows changes to system-wide settings such as interfaces, routing protocols, and VLANs.

EXEC Mode:Has two levels—User EXECandPrivileged EXEC. User EXEC provides limited diagnostic commands, while Privileged EXEC allows more extensive system views (show commands, reload, etc.).

Understanding these layers is essential when maintaining or restoring NX-OS devices in field environments.

Cisco Webex Callingis a cloud-based, enterprise-grade PBX (Private Branch Exchange) solution designed to provide comprehensive voice communication services via the Webex cloud platform. It enables IP phones and softphones to register to the cloud, allowing for centralized call control, voicemail, and collaboration features without the need for an on-premises call manager.

Cisco Hosted Collaboration Solutionsare partner-hosted services.

Webex Meetingssupports virtual video conferencing.

Webex Teams(now part of Webex App) supports messaging and collaboration, not PBX functionality.

The commandcopy tftp: running-configis used to retrieve a configuration file from a TFTP server and merge it with the current running configuration of a Cisco device. Thisoperation is additive, meaning it integrates the new configuration commands into the existing running configuration without removing any pre-existing commands unless explicitly overridden.​

This method is particularly useful when restoring configurations to a replacement device, as it allows for the seamless integration of necessary settings without disrupting the current operational state.​

In contrast, usingcopy tftp: startup-configwould overwrite the startup configuration file, which could lead to unintended consequences upon the next device reload. The optionsload tftp: running-configandmerge tftp: running-configare not valid Cisco IOS commands.​

Before shutting down any Cisco collaboration device (such as an IP phone, video endpoint, or codec) for replacement, it is essential toback up the configuration. This ensures that all custom settings, including user profiles, network configurations, and service settings, are preserved and can be quickly restored on the replacement device.

This backup minimizes downtime and avoids manual reconfiguration errors during the swap process.

In the hierarchical network design model, theaccess layeris the first layer and serves as the entry point for end-user devices to connect to the network. This layer connects user devices such as PCs, IP phones, wireless access points, printers, and scanners to the network. It facilitates the initial connection between end-user devices and the network infrastructure. The access layer also enforces security policies and provides services such as VLAN membership, port security, and Quality of Service (QoS).​

Options A, C, and D refer to functions typically associated with the core or distribution layers, or with WAN connectivity, rather than the access layer.​

To ensure asmooth replacementof a Cisco UCS C-Series Rack-Mount Server, two critical actions are:

Back up the server configuration using the Cisco Integrated Management Controller (CIMC): This preserves all configuration data such as BIOS settings, RAID setup, and network configuration. After replacing the hardware, this configuration can be restored to minimize setup time.

Decommission the server if it is integrated in a Cisco UCS domain: Before physically replacing the server, decommissioning it ensures the UCS Manager properly releases it from the inventory, preventing configuration conflicts or orphaned profiles.

Other options, like reconfiguring DHCP or disabling firewalls, are not required procedures for a UCS C-Series hardware swap.

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.​