Day 3 - Trunking, DTP, and Inter-VLAN Routing Flashcards
What is DTP?
Dynamic Trunking Protocol
Define a trunk
A trunk is a switch port that can carry multiple traffic types, each tagged with a unique VLAN ID.
What is the first configuration task when implementing VLAN trunking?
To configure the desired interface as a Layer 2 switch port.
What is the command to configure an interface as a Layer 2 switch port?
the switchport command
When is the switchport command required?
on Layer 3 capable switches
What is the second configuration task when implementing VLAN trunking?
Specify the encapsulation protocol.
What is the command to specify the encapsulation protocol for a trunk link?
switchport trunk encapsulation [option]
What are the three options for the switchport trunk encapsulation command?
dot1q
isl
negotiate
What is dot1q encapsulation?
forces the switch to use IEEE 802.1Q encapsulation.
What is isl encapsulation?
forces the switch to use ciscos ISL encapsulation
What is negotiate encapsulation?
specifies that if Dynamic Inter-Switch LInk Protocol (DISL) and the Dynamic Trunking Protocol (DTP) negotiation fails to agree on the encapsulation, then ISL is the selected format.
What is DISL?
Dynamic Inter-Switch Link protocol
What is DTP?
Dynamic Trunking Protocol
What command would you use to validate proper trunking configuration?
show interface [name]
What is the third trunk port configuration step?
to implement configuration to ensure that the port is designated as a trunk port.
What are the two ways to designate a port as a trunk port?
Manual (static) trunk configuration
Dynamic Trunking Protocol (DTP)
What is the command for manual configuration of a port for trunking?
switchport mode trunk
What command would you use to validate manual port trunking configuration?
show interfaces [name] switchport
It is a good practice to disable the sending of DISL and DTP packets on a statically configured trunk port. What is the command to do this?
switchport nonegotiate
What are the two DTP modes that a switch port can use?
Dynamic desirable
Dynamic auto
If two switches are each set to dynamic auto will they establish a trunk between them or not?
they will not because dynamic auto mode is passive
What is the command to see dynamic trunking protocol information both globally and for a specific interface?
show dtp
show dtp [interface ]