2 - Ethernet LANs Flashcards
What is the default baud rate for a console port?
9600 bits/second
What are the default console port settings?
9600 baud. No hardware flow control. 8N1 (8bit ASCII, No parity bits, 1 stop bits)
What are three common CLI access methods?
Console, Telnet, SSH
What is another name for User mode?
EXEC mode
What is another name for privileged mode and what console prompt denotes this mode?
Enable mode. #
What mode do you have to be in to reload a switch?
Enable mode
What two points in the login process can you configure simple passwords for?
- When the user connects from the console
2. When any user moves to Enable mode
What command is used to set a password to enter Enable mode?
enable secret password123
What commands would you use to set a password on the console line?
line console 0
login
password password123
How do you move from Enable mode to Global Config mode?
Use the config
command
What command do you use to move back to Global Config mode from other sub-command modes?
exit
Where are Cisco IOS images stored by default on devices?
Flash memory
Where is the startup configuration file stored?
NVRAM
Where is the bootstrap / boot-helper program stored?
ROM
What does the bootstrap program do?
Finds the full Cisco IOS image and manages the process of loading the IOS into RAM
What are three commands you can use to erase the startup config file?
erase startup-config
write erase
erase nvram:
How does a Switch learn a MAC address?
By examining the source address of the frame it receives from a device
What is the CAM table?
Memory construct on switches to store a MAC address and the associated physical port it is on. Also stores the VLAN number
What are two alternative names for the CAM table?
Switching table. Bridging table
What does a switch do with a frame it receives for a destination not yet in the CAM table?
Floods the frame out all ports except the one it was received on, with an Ethernet broadcast address of FF:FF:FF:FF:FF:FF
What are the three primary features of LAN switches?
- Forward / filter Ethernet frames
- Preparing to forward frames by learning MACs
- Prevent network loops (STP)
What does STP do?
Prevent network loops by blocking some ports from forwarding frames so that only one active path exists between any pair of LAN segments. Without it, frames could loop indefinitely, flooding process can completely congest LAN
What is the default VLAN for Cisco switches?
VLAN 1
What command is used to show the MAC address table on a Switch?
show mac address-table
How would you show all Dynamically added MACs on a Switch?
show mac address-table dynamic
What command would delete VLAN configuration details on a Switch?
delete vlan.dat
What does the Type column show in the output of show mac address-table on a switch?
How the MAC was learned, e.g. dynamically or static (entered manually)
How do VLANs impact switching logic?
For a given port, the Switch generally only forwards out frames on the VLAN that port is on
What command could you use to show the status of interfaces on a Switch?
show interfaces status
What command shows statistics about incoming and outgoing frames on interfaces?
show interfaces f0/1 counters
How do you view the details in a MAC address table for just a specific MAC, specific interface, and specific VLAN?
show mac address-table dynamic address 0200.1111.1111
show mac address-table dynamic interface f0/1
show mac-address-table dynamic vlan 1
What does a Switch do with respect to an incoming frame and aging?
Examine the source MAC, reset the inactivity timer back to 0 for that MACs entry
What command is used to change the MAC address table aging timer?
mac address-table aging-time [vlan vlan-no]
What does a Switch do when it needs to add a new MAC table entry but the table is full?
Removes the oldest entry, even if it is younger than the aging time setting
How do you remove a dynamic entry from a MAC table
clear mac address-table dynamic
- vlan
- interface
- address
What are the three main planes of a networking device?
Data plane
Control plane
Management plane
What is the main function of the data plane of a Switch?
The work done to forward frames generated by devices connected to the Switch. The main purpose of the switch.