Cisco CCNA - Switching Routing & Wireless Essentials Module 1-4 practice questions

What is the boot sequence of a Cisco Switch?

• POST

• Switch loads boot loader

• Boot loader performs low-level CPU initialization

• Boot loader initializes flash file

• Boot loader locates and loads the IOS operating system.

Which part of the boot system command does this describe?
“Boot System”

The main command

Which part of the boot system command does this describe?
“flash:”

The Storage Device

Which part of the boot system command does this describe?
“c2960-lanbasek9-mz.150-2.SE/”

the path to the file system

Which part of the boot system command does this describe?
“c2960-lanbasek9-mz.150-2.SE.bin/”

The IOS file name

blank and blank require full-duplex connections to operate.

• Gigabit Ethernet

• 10Gb NICs

Which command is used to enter Global Configuration Mode?

configure terminal

Which command is used to enter Interface Configuration Mode

Interface interface #

Which command is used to configure the interface duplex?

duplex full

Which command is used to configure the interface speed?

speed #

Which command is used to reenter privileged EXEC mode?

end

Which command is used to save the running config to the startup config

copy running-config startup-config

Which command is used to configure Auto-MDIX?

mdix auto

What command can be issued to validate if Auto-MDIX is configured on a port?

show controllers ethernet-controller port # phy | include MDIX

Which command is used to display the MAC address table?

show mac address-table OR show mac-address-table

Which command is used to display information about the flash file system?

show flash

Which command displays the system hardware and software status?

show version

which command shows the history of commands entered?

show history

What are Input Errors?

Total number of errors, includes runts, giants, CRC, no butter, frame, overrun, and ignored counts

What are Runts?

frames that are discarded because they’re too small (smaller than minimum frame size).

What are Giants?

Frames that are discarded because they exceed the max frame size.

what is CRC?

generated when the calculated checksum is not the same as the received checksum.

what are output errors?

sum of all errors that prevented final transmission out of the interface to be examined.

what are Collisions?

number of messages retransmitted.

what are Late Collisions?

A collision that occurs after 512 bits of the frame have been transmitted.

How do you activate SSH on a switch?

Transport input SSH

How do you configure/enable Telnet on a switch?

Transport Input Telnet

What steps are required to enable SSH?

• verify SSH support

• configure IP

• configure IP domain

• generate RSA key pairs

• configure user authentication

• configure VTY lines

• enable SSH version 2

What command enables SSH version 2?

IP ssh version 2

what command generates RSA key pairs?

crypto key generate RSA

Ingress

Used to describe the port where a frame enters the device

Egress

used to describe the port frames will use when leaving the device

store-and-forward switching

Switching method that makes a forwarding decision on a frame after it has received the entire frame and checked it for errors.

Cut-through switching

This method begins forwarding the frame after the destination MAC of the incoming frame and the egress port have been determined.

error checking

After receiving an entire frame from the ingress port, the switch compares the FCS value in the last field of the datagram to its own FCS calculations. If the frame is error free, the switch forwards the frame, if not, it drops it.

Automatic Buffering

The ingress port buffering process used by store-and-forward switches provides the flexibility to support any mix of Ethernet speeds.

Collision Domains

Switches eliminate these and reduce congestion.

Broadcast Domain

Extends across all layer 1 or layer 2 devices on a LAN

Fast Port Speeds Protocol

Depending on the model, switches may have up to 100Gbps port speeds.

Fast Internal Switching Protocol

This uses fast internal bus or shared memory to improve performance

Large Frame Buffers protocol

This allows for temporary storage when processing large quantities of frames

High Port Density Protocol

This provides many ports for devices to be connected to LAN with less cost. Also provides more local traffic with less congestion.

Which information does a switch use to keep the MAC address table information current?

The source MAC address and the incoming port.

What does the term "port density" represent for an Ethernet switch?

The number of available ports

Which type of address does a switch use to build the MAC address table?

Source MAC address

Which network device can be used to eliminate collisions on an Ethernet network?

Switch

What is the purpose of frame buffers on a switch?

They hold traffic, alleviating network congestion.

Which switch characteristic helps alleviate network congestion when a 10 Gbps port is forwarding data to a 1 Gbps port?

Frame Buffering

What is one function of a Layer 2 switch?

Determines which interface is used to forward a frame based on the destination MAC address

Which statement is true about broadcast and collision domains?

Adding a switch to a network will increase the size of the broadcast domain.

VLAN Trunks

Allow VLAN traffic to propagate between switches. This enables devices to be connected to different switches but in the same VLAN.

Type

A 2-byte value called the tag protocol ID (TPID) value. For Ethernet, it is set to hexadecimal 0x8100.

User priority

A 3-bit value that supports level or service implementation

Canonical Format Identifier (CFI)

a 1-bit identifier that enables Token Ring frames to be carried across the network.

VLAN ID (VID)

A 12-bit identification number that supports up to 4096 VLAN IDs

switchport mode access

Set the port to access mode

switchport access vlan vlan id

Assign the port to a VLAN

What command is used to enable QoS?

mls qos trust cos

how do you display VLAN summary?

show vlan summary

how do you assign a voice VLAN to a port?

switchport voice vlan 150

How do you set a port to permanent trunking mode?

switchport mode trunk

How do you change the native VLAN id?

switchport mode trunk native vlan vlan-id

How do you specify the list of VLANs allowed to be on the trunk link?

switchport trunk allowed vlan vlan-list.

how do you remove permanent trunking from a port?

no switchport trunk allowed vlan

how do you remove the native trunk from a port?

no switchport trunk native vlan

What command excludes a port from participating in DTP negotiation?

switchport nonegotiate

What command is used to re-enable Dynamic Trunking Protocol?

switchport mode dynamic auto

What is the proprietary protocol on Cisco Switches that lets them automatically negotiate trunking with a neighboring device?

Dynamic Trunking Protocol

What does the command, “Switchport mode Dynamic Desirable” do?

makes the interface actively attempt to convert the link to a trunk link.

What happens to a port that is associated with VLAN 10 when the administrator deletes VLAN 10 from the switch?

the port becomes inactive

An administrator is investigating a failure on a trunk link between a Cisco switch and a switch from another vendor. After a few show commands, the administrator notices that the switches are not negotiating a trunk. What is a probable cause for this issue?

Switches from other vendors do not support DTP.

What is the purpose of the vlan.dat file on a switch?

it holds the VLAN database.

When a Cisco switch receives untagged frames on a 802.1Q trunk port, which VLAN ID is the traffic switched to by default?

Native VLAN ID

A network administrator is determining the best placement of VLAN trunk links. Which two types of point-to-point connections utilize VLAN trunking?​ (Choose two.)

• Between two switches that utilize multiple VLANs

• Between a switch and a server that has an 802.1Q NIC

On a Cisco switch, where is extended range VLAN information stored?

running configuration file

In which location are the normal range VLANs stored on a Cisco switch by default?

Flash memory

For what reason would a network administrator use the show interfaces trunk command on a switch?

To view the native VLAN

What is the most acceptable Inter-VLAN solution for a small to medium-sized network?

Router-on-a-Stick

What is the most acceptable Inter-VLAN routing solution for scalability?

Switch Virtual Interfaces (SVIs)

What is the purpose of Layer 3 Inter-VLAN Routing?

It is very scalable and can convert a layer 2 switchport to a layer 3 interface.

What command enables IP Routing?

ip routing

What are the 4 common Inter-VLAN issues?

• Missing VLANs

• Switch Trunk Port issues

• Switch Access Port Issues

• Router Configuration Issues