Lab Objective:
The objective of this lab exercise is for you to learn and understand how to set the auto-negotiation type on a trunk link.
Lab Purpose:
Switch interfaces are set to automatically attempt to create a trunk link when connected to another switch. You need to know how to set either dynamic desirable or dynamic auto.
Certification Level:
This lab is suitable for CCENT exam preparation.
Lab Difficulty:
This lab has a difficulty rating of 5/10.
Readiness Assessment:
When you are ready for your certification exam, you should complete this lab in no more than 10 minutes.
Lab Topology:
Please use the following topology to complete this lab exercise:
Task 1:
In preparation for the configuration, configure a hostname on Sw1 as well as Sw2.
Task 2:
Configure Sw1 so that auto-negotiation of trunking is set to dynamic auto.
Task 3:
Configure Sw2 so that auto-negotiation of trunking is set to dynamic desirable.
Task 4:
Verify your configurations with the appropriate show commands (illustrated in Task 3 below).
Configuration and Verification
Task 1:
For reference information on configuring hostnames, please refer to earlier labs.
Task 2:
Sw1#show int fast0/1 switchport Name: Fa0/1 Switchport: Enabled Administrative Mode: dynamic auto Operational Mode: static access Administrative Trunking Encapsulation: dot1q Operational Trunking Encapsulation: native Negotiation of Trunking: On Access Mode VLAN: 1 (default) Trunking Native Mode VLAN: 1 (default)
The interface is actually already set to dynamic auto, which is the default setting for this model of switch (yours may vary). Let’s put the command in anyway.
Sw1(config)#int fast0/1 Sw1(config-if)#switchport mode dynamic auto
Task 3:
NOTE: You need to have at least one switch set to either trunk or dynamic desirable for a trunk link to form.
Sw2#show int fast0/1 sw Name: Fa0/1 Switchport: Enabled Administrative Mode: dynamic auto Operational Mode: static access Administrative Trunking Encapsulation: dot1q Operational Trunking Encapsulation: native Negotiation of Trunking: On Access Mode VLAN: 1 (default) Sw2#show interface trunk Sw2(config)#int fast0/1 Sw2(config-if)#switchport mode dynamic desirable Sw2(config-if)#end Sw2#show int fast0/1 switchport Name: Fa0/1 Switchport: Enabled Administrative Mode: dynamic desirable Operational Mode: trunk Administrative Trunking Encapsulation: dot1q Operational Trunking Encapsulation: dot1q Negotiation of Trunking: On Access Mode VLAN: 1 (default) Trunking Native Mode VLAN: 1 (default) Sw2#show interface trunk Port Mode Encapsulation Status Native vlan Fa0/1 desirable n-802.1q trunking 1
The n indicates that it negotiated the encapsulation type.