Examkin

Soru

Zorluk: OrtaInterswitch Connectivity and Trunking (802.1Q)

A network engineer configures interface GigabitEthernet0/1 on Switch-1 with the commands `switchport mode trunk` and `switchport nonegotiate`. The connected interface GigabitEthernet0/1 on Switch-2 remains in its default configuration of `switchport mode dynamic auto`. What is the resulting operational state of interface GigabitEthernet0/1 on Switch-2?

  1. It operates as an access port because it does not receive Dynamic Trunking Protocol (DTP) frames from Switch-1 to trigger trunk negotiation.Cevap
  2. B
    It automatically negotiates an 802.1Q trunk because CDP detects that Switch-1 has trunking enabled on the interface.
  3. C
    It generates continuous native VLAN mismatch error messages because DTP is disabled on Switch-1.
  4. D
    It enables PortFast on the trunk link to establish forwarding without requiring DTP frames.

Cevap

Interface GigabitEthernet0/1 on Switch-2 operates as an access port because `switchport nonegotiate` on Switch-1 suppresses DTP frames, leaving Switch-2 in its default passive access state.
The command `switchport nonegotiate` turns off DTP frame generation on Switch-1. Because interface GigabitEthernet0/1 on Switch-2 is set to `dynamic auto`, it relies on receiving incoming DTP negotiation frames to transition to a trunking state. Receiving no DTP frames from Switch-1, Switch-2 stays in its default operational mode of access, resulting in a misconfiguration where Switch-1 trunks while Switch-2 acts as an access port.

Adım Adım Çözüm

1
Analyze the DTP configuration on Switch-1
Switch-1 is configured statically as a trunk (`switchport mode trunk`) and DTP frame transmission is disabled using `switchport nonegotiate`.
The `nonegotiate` command stops the interface from sending DTP frames to neighboring devices.
2
Analyze the DTP operational behavior on Switch-2
Switch-2 is in `switchport mode dynamic auto`, which means it will form a trunk only if it receives a DTP request frame (desirable or trunk mode) from the remote switch.
Dynamic auto interfaces never actively originate DTP negotiation requests; they remain passive.
3
Determine the resulting link operational state
Because Switch-1 sends no DTP frames, Switch-2 never receives the signal to become a trunk and defaults to an operational access port.
A link connecting a static trunk with `nonegotiate` to a `dynamic auto` interface creates a mode mismatch where one side is trunking and the other is an access port.

Anahtar Kavram

802.1Q Trunking DTP Negotiation and Nonegotiate Interaction
Bu soruyu puanla

Konular

Interswitch Connectivity and Trunking (802.1Q)

Bu konudan daha fazla soru