PrepAwayPDF 100-490 Exam Questions Real 100-490 Practice Dumps [Q10-Q28]

Section: Cisco IOS Software Operation

RJ-45 is the standard connector used for Ethernet networks. Here’s why it’s the correct answer:
Compatibility: Ethernet ports on both laptops and Cisco switches use RJ-45 connectors. This makes RJ-45 cables ideal for direct connections between these devices.
Appearance: RJ-45 ports are rectangular and slightly larger than typical phone jacks (RJ-11). They have eight metal pins inside.
Why other options are incorrect:
DVI: DVI ports are used for video connections between computers and displays.
RJ-11: RJ-11 ports are primarily associated with analog phone lines and are smaller than RJ-45.
DB-9: DB-9 connectors were traditionally used for serial connections on older computers and peripherals.

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.

The Cisco Nexus 3432D-S and Cisco Nexus 3408-S are part of the Cisco Nexus 3400 Series switches that support 400-Gbps Ethernet ports. The Cisco Nexus 3432D-S is designed with 32 ports of 400G, providing high-density and high-throughput capabilities1. The Cisco Nexus 3408-S offers flexibility with 100G or 400G Line-Card Expansion Modules (LEMs), allowing for configurations with 32 ports of 400G2. These switches are engineered for data centers requiring high performance, low latency, and power efficiency, with the Cisco Nexus 3432D-S offering industry-leading performance-per-watt power efficiency at low latency1.

Section: General Networking Knowledge

While the initial answers focused on the most common causes, here’s why the other options could also contribute to an interface being stuck in the “up/down” state:
A . Speed or Duplex Mismatch: Devices on either end of an Ethernet connection need to use compatible speed (e.g., 100 Mbps, 1 Gbps) and duplex (full-duplex or half-duplex) settings. Mismatches can prevent the line protocol from coming up even if the physical link is established.
B . Layer 2 Mismatch in Encapsulation Type: Some protocols used on Ethernet networks, like ISL and 802.1Q, have specific encapsulation requirements. If devices on each end aren’t using the same encapsulation type, the line protocol will likely remain down.
C . The Ethernet Interface Has Been Manually Disabled: Correct! Administrators can put an interface in a shutdown state using commands like shutdown. This brings down the line protocol even if the physical connection is good.
D . Keepalives Are Not Being Received by the Local Device: While less likely to be the sole cause, issues with keepalive mechanisms used in some routing protocols could potentially lead to the line protocol going down. If the local device expects keepalives and doesn’t receive them, it might assume a connectivity problem and affect the interface status.
E . The Ethernet Cable Might Not Be Attached Properly: While a disconnected or faulty cable would usually make the interface down/down, it’s possible in some scenarios for a partially connected or damaged cable to result in a link being detected (Layer 1 up) but with errors preventing the line protocol (Layer 2) from initializing.
Troubleshooting network issues often involves considering multiple factors and testing different possibilities. The “up/down” status gives important clues but might have several potential root causes.

USB thumb drives (also called flash drives) serve several practical purposes in networking:
File Transfer: They are excellent for transferring Cisco router or switch configuration files between the device and a PC. This allows you to back up configurations, easily restore configurations, or work with them offline.
IOS Image Storage: USB thumb drives are convenient for storing and transferring Cisco IOS images, especially when you need to upgrade or recover network devices.
Why other options are incorrect:
to save the system log: While you might temporarily store log files on a USB drive, routers and switches generally utilize internal memory or a remote syslog server for logging purposes.
to save router hardware information: Hardware inventory information obtained from commands like show inventory is often copied and pasted to text files, which can then be stored on a USB drive. However, the drive itself doesn’t directly save or store this hardware information.
to increase system memory: USB drives are not designed to act as additional system memory (RAM) for a router or switch.

Section: Cisco IOS Software Operation

IPv4 addresses consist of four octets, each ranging from 0 to 255. The addresses are used to uniquely identify devices on a network.
A . 255.255.255.255 is reserved for broadcast messages to all hosts on the local network, so it cannot be assigned to a single host.
B . 10.1.1.20 falls within the range of private IP addresses (10.0.0.0 to 10.255.255.255) and can be assigned to a host within a private network.
C . 0.0.0.0 is used to denote an unknown or non-applicable target address, often used as a default route, and cannot be assigned to a host.
D . 192.168.10.15 is also within the range of private IP addresses (192.168.0.0 to 192.168.255.255) and can be assigned to a host within a private network.
E . 292.10.3.4 is not a valid IPv4 address because the first octet exceeds the maximum value of 255.
Reference:
IPv4 Addressing
Valid IP Address
IP Address Validation

The commands to copy a saved configuration to RAM on Cisco devices are:
copy startup-config running-config: This command is used to copy the startup configuration (saved configuration) into the running configuration (current configuration in RAM). It is typically used when you want to restore the device to a previously saved configuration after changes have been made1.
copy tftp running-config: This command allows you to copy a configuration file from a TFTP server directly into the running configuration of the device. It’s useful for applying a new configuration or for restoring a configuration from a backup located on a TFTP server1.
The other options listed are not valid for copying a saved configuration to RAM:
copy running-config startup-config copies the current running configuration to the startup configuration, which is the opposite of what’s asked.
copy running-config tftp is used to save the running configuration to a TFTP server, not to copy to RAM.
copy tftp startup-config would copy a file from a TFTP server to the startup configuration, not to the running configuration in RAM.

Section: Cisco Equipment and Related Hardware
Explanation/Reference: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus3400s/sw/922/interfaces/ configuration/guide/b_Cisco_Nexus_3400_NX-OS_Interfaces_Configuration_Guide_922/ b_Cisco_Nexus_3400_NX-OS_Interfaces_Configuration_Guide_9z_chapter_010.html

Section: Service-related Knowledge

IPv6 addresses are 128 bits in length and are written as eight groups of four hexadecimal digits. Each group is separated from the others by colons (:). The correct notation for IPv6 addresses allows for the omission of leading zeros within each block of four hexadecimal digits and the use of double colons (::) to represent consecutive blocks of zeros. However, the double colons can only be used once in an address to ensure proper expansion to the full 128 bits. Option B is the only choice that correctly represents a full IPv6 address without any abbreviation. Options A and C use double colons incorrectly, and option D represents a prefix length rather than a full address. Reference := The information is based on standard IPv6 address notation practices, which include the representation of addresses in hexadecimal format and the rules for abbreviating zeros1

The tftpdnld command is specifically designed to initiate a TFTP (Trivial File Transfer Protocol) transfer of an image within ROMmon mode on a Cisco device. Here’s why it’s the correct answer:
ROMmon Functionality: ROMmon (Read-Only Memory Monitor) is a basic operating system mode used when the main Cisco IOS is unavailable. The tftpdnld command works from ROMmon to download a new IOS image.
TFTP Protocol: The tftpdnld command utilizes TFTP, which is a simple and reliable protocol commonly used for transferring Cisco IOS images.
Purpose: The command is used primarily for recovering corrupt images or upgrading to a different IOS version.
Why other options are incorrect:
Xmodem: XMODEM is an older and less reliable file transfer protocol that’s less suitable than TFTP for Cisco IOS image transfers.
copy tftp: flash: This command format is used within the Cisco IOS itself, not in ROMmon mode.
copy flash: tftp: This command format would attempt to upload an image from flash memory to a TFTP server, instead of downloading an image.

Rollover cables are specifically designed for connecting to the console ports on Cisco routers and switches. Here’s why they are the right choice:
Pinout: Rollover cables have a reversed pinout compared to standard Ethernet cables. This matches the console port’s wiring, allowing for configuration access.
Appearance: Rollover cables are often light blue in color to help distinguish them from standard Ethernet cables.
USB Adapter: Many modern laptops may not have a direct serial port. In this case, a rollover cable with a USB-to-serial adapter is used.
Why other options are incorrect:
Straight-through: Used for connecting unlike devices (e.g., switch to computer). They won’t have the correct wiring for console connections.
Fiber: Used for high-speed, long-distance networks. Console ports use a serial-based connection, not fiber optics.
Crossover: Used to connect similar devices (e.g., switch to switch). The pinout is not the same as what a console port requires.

Cisco NX-OS has added support for Python scripting to help manage user networks. Python is a powerful and versatile scripting language that is widely used for automation tasks, including network management. Cisco NX-OS leverages Python to enable network administrators to write custom scripts and programs that can interact with the network operating system, automate repetitive tasks, and integrate with other systems and APIs. This support for Python scripting is part of Cisco’s commitment to network programmability and automation, allowing for more efficient and flexible network operations12.

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.
Reference:
Cisco Networking Academy: Introduction to Networks Course

Section: Cisco IOS Software Operation
Explanation