Home » Cisco » 300-115 » Which IOS commands are entered in interface configuration mode to configure a switch port to unconditionally be an 802.1Q trunk port and not generate DTP packets?
Which IOS commands are entered in interface configuration mode to configure a switch port to unconditionally be an 802.1Q trunk port and not generate DTP packets? (Choose two.)
A. trunk dot1q
B. switchport trunk dot1q
C. switchport nonegotiate
D. switchport trunk allowed vlan
E. switchport trunk encapsulation dot1q
Correct Answer: CE
Explanation/Reference:
Answer:
Entering the IOS commands switchport nonegotiate and switchport trunk encapsulation dot1q in interface configuration mode will only allow a switch port to be an 802.1Q trunk port. This disables the generation of dynamic trunking protocol (DTP) negotiation packets. Since DTP also negotiates encapsulation type, the encapsulation type must be identified (for example, dot1q).
Use the following steps to configure a port as an 802.1Q trunk:
1. Enter the interface configuration: switch(config)# interface interface-id
2. Configure the port to using 802.1Q encapsulation: switch(config-if)# switchport trunk encapsulation dot1q
3. Configure the port as a trunk port: switch(config-if)# switchport nonegotiate
Note: Trunking modes can be configured as trunk, dynamic auto, dynamic desirable, nonegotiate, and access.
The switchport allowed vlan command is also valid for configuring dot1q trunks, but is not required. By default, all VLANs are allowed on the trunk.
Objective:
Layer 2 Technologies Sub-Objective:
Configure and verify trunking
References:
Cisco > Cisco IOS Interface and Hardware Component Command Reference > squelch through system jumbomtu > switchport trunk Cisco > Cisco IOS Interface and Hardware Component Command Reference > I through K > interface
