Cisco Supporting Cisco Routing & Switching Network Devices 100-490 RSTECH Exam Questions

Answer : D

The copy startup-config running-config command is used during the password recovery process on a Cisco router to load the saved configuration into the device's active running configuration. Here's why this is the correct choice:

Password Recovery Context: Password recovery often involves booting into ROMmon mode and changing the configuration register to bypass the normal boot process. This leaves the device with a blank running configuration.

Restoring Configuration: The copy startup-config running-config command copies the stored configuration (startup-config) from NVRAM into the running-config, which is used by the router for its operations.

Why other options are incorrect:

load_helper: While the load_helper command sometimes appears in password recovery procedures, it's typically used for older models and may not be necessary for all Cisco routers.

configure terminal: This command simply enters global configuration mode. It doesn't directly load a configuration.

copy running-config startup-config: This command saves the active running configuration into NVRAM as the startup-config. It's the reverse of what you need for password recovery.

Answer : C

A Cisco router can be configured to act as a TFTP (Trivial File Transfer Protocol) server. TFTP is a simple protocol used to transfer files without the need for authentication. On a Cisco router, the tftp-server command is used to designate the router as a TFTP server, allowing it to manage file transfers to and from connected devices. This is particularly useful for tasks such as updating the router's firmware or backing up configuration files. Neither CSU/DSU, modem, nor Cisco Content Engine are typically used as TFTP servers. Reference := The ability to configure a Cisco router as a TFTP server is documented in Cisco's support forums and knowledge base articles

Answer : A, E

SmartJacks are specialized devices used in telecommunications, particularly for T1/E1 lines. Here's why the correct answers make sense:

Signal Conversion: SmartJacks can convert between different signaling types (e.g., AMI to B8ZS). This is necessary because different telecommunication lines may use varying signaling standards.exclamation

Signal Regeneration: As signals travel over long distances, they can weaken and degrade.expand_more SmartJacks help regenerate the signal, ensuring that it maintains its strength and integrity throughout the transmission.expand_more

Why other options are incorrect:

Concentration point: SmartJacks are not primarily used as concentration points for dial-in/out connections.exclamation This function is typically handled by modems or other specialized devices.exclamation

Layer 2 operation: SmartJacks primarily operate at Layer 1 (Physical Layer) of the OSI model, focusing on the physical transmission of signals.

Channel Testing: While some SmartJacks may offer some basic channel testing capabilities, their primary functions are signal conversion and regeneration.

SmartJack (Wikipedia): https://en.wikipedia.org/wiki/Smartjack

Answer : B

Microsoft Notepad is the preferred text editor for working with Cisco configuration files and other simple text documents for several reasons:

Plain Text Focus: Notepad is designed specifically for plain text editing. It does not add any formatting, hidden characters, or metadata that could interfere with the configuration file's structure.

Cisco Syntax Compatibility: Cisco configurations rely on specific syntax and spacing. Notepad preserves these elements accurately.

Universality: Notepad is a basic text editor included in all versions of Windows, ensuring accessibility and eliminating the need for additional software.

Why other options are not ideal:

Microsoft Word: Word is a word processor and includes formatting, fonts, and other features that are not compatible with Cisco configuration files. This formatting can corrupt the configuration.

Microsoft Access: Access is a database management system, not suited for text file editing.

Microsoft Excel: Excel is a spreadsheet application and adds its own structure and formatting that conflicts with configuration file formats.

Answer : C

The tftpdnld command in Cisco IOS is specifically designed for recovering or upgrading a system image. Here's how it's the most effective method:

Purpose: The tftpdnld command directly initiates a TFTP download of a new system image and stores it in memory. This is ideal for replacing a corrupt image or upgrading to a newer version of Cisco IOS.

ROMmon: The tftpdnld command can often be used from ROMmon mode, which is essential when the existing image is unusable.

Efficiency: It streamlines the image transfer process specifically using TFTP, which is commonly used for Cisco IOS images.

Why other options are less ideal:

USB storage: While some newer Cisco devices may allow direct loading of an IOS image from USB, this isn't universally supported and often requires specific boot commands.

FTP: FTP (File Transfer Protocol) can be used for file transfers, but it's not as commonly used as TFTP in the context of Cisco IOS image recovery. The tftpdnld command offers a more tailored solution for this purpose.

the xmodem command: XMODEM is a legacy file transfer protocol that is slower and less reliable than TFTP, especially for larger files like Cisco IOS images.

Answer : B, D

Loopback plugs are used to test the physical connections and configurations of network equipment. In a 56K modem loopback plug, the following pins are looped to create a test signal:

Pins 1 and 7 (Transmit): Looping the transmit pins back to each other allows the device to test its own signal transmission.

Pins 2 and 8 (Receive): Looping the receive pins back to each other allows the device to test its ability to receive its own signal.

Understanding RJ-45 Wiring:

RJ-45 connectors are standardized and have a specific pinout for various applications like Ethernet networking and analog telephony connections. You can find resources online that show the standard RJ-45 color coding and pin assignments.

Answer : C

Straight-through cables are the most common type of Ethernet cable. They're used to connect dissimilar devices, such as a laptop to a router or a switch to a router. The internal wiring of the cable connects the transmit pins on one end to the receive pins on the other end, and vice versa.

Crossover cables were historically necessary to connect similar devices (e.g., router to router, or switch to switch). Modern devices often have auto MDI-X capabilities, allowing them to automatically detect and adjust to straight-through or crossover connections as needed.

Rollover cables have a reversed pinout and are primarily used for console access into Cisco routers and switches.

Fiber cables use fiber optic technology for high-speed, long-distance connectivity.

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