cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1770
Views
0
Helpful
3
Replies

default setting of dtp on switches

sarahr202
Level 5
Level 5

Hi everybody.

Let say we have two brand switches ,sw1 and sw2  and we connect them as : 

s1-----------s2

will trunk form between them?

In other words  is dtp enabled on switch port by default or do we need to configure it as " switchport mode  dynamic desirable/auto" ?If yes  then what mode i.e auto dynamic desirable

thanks and have a great weekend

1 Accepted Solution

Accepted Solutions

Hi Sarah,

Hope you well and congrats on your Route exam.

Now to your question. The switchports are in  a state of "dynamic desirable" out of the box. So if you just connect them with a cat cable, you will see the trunk would be formed. and yes DTP is enabled in the dynamic desirable mode and that's how the switches negotiate to become a trunk.

The best way to see what mode the ports are would be type the command " sh interfaces switchport" Look for the administrative/operational mode.options

HTH

Kishore

View solution in original post

3 Replies 3

John Blakley
VIP Alumni
VIP Alumni

if they're Cisco switches, then yes a trunk is formed because of the dynamic desirable mode on both ends of the link. If its a non-Cisco switch on either end, a trunk won't form automatically that I'm aware of. Usually you have to hard code the mode to trunk on the Cisco switch and the same the on te other side. Then you would disable DTP by setting switchport nonegotiate on the link that connects to the other switch.

Sent from Cisco Technical Support iPhone App

HTH, John *** Please rate all useful posts ***

Hi Sarah,

Hope you well and congrats on your Route exam.

Now to your question. The switchports are in  a state of "dynamic desirable" out of the box. So if you just connect them with a cat cable, you will see the trunk would be formed. and yes DTP is enabled in the dynamic desirable mode and that's how the switches negotiate to become a trunk.

The best way to see what mode the ports are would be type the command " sh interfaces switchport" Look for the administrative/operational mode.options

HTH

Kishore

Thanks Kishore

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: