
Unless the operation of [DTP](/dtp) is completely [disabled](/dtp-how-to-disable), a switchport will always send out DTP messages regardless of the [mode](/switchport-modes) it has been configured with.

For example, even though the switchport mode dynamic auto is passive in terms of initiating a [trunk](/switchport-trunk) negotiation, it still sends out DTP frames.  


Links:

https://forum.networklessons.com/t/cisco-dtp-dynamic-trunking-protocol-negotiation/1083/34?u=lagapidis

https://networklessons.com/switching/cisco-dtp-dynamic-trunking-protocol-negotiation/

DTP - Sending of Frames

DHCP client options on Cisco IOS

DHCP decline message

DHCP excluding address on a Cisco IOS DHCP server

DHCP multiple IP helper-addresses

DHCP multiple servers on the same subnet

DHCP offer message sent as broadcast

DHCP option 82

DHCP relay agent

DHCP relay support for MPLS VPN

DHCP renewal rebinding

DHCP snooping rate limiting best practice

DHCP trusted and untrusted ports

DHCP

DHCPv6 - determining the IPv6 prefix assigned to an interface

DHCPv6 lease times on a Cisco IOS device

DHCPv6 relay agent

DMVPN - IPsec encryption order of operations

DMVPN - NHRP purge request

DMVPN - NHRP session attributes

DMVPN - OSPF and multiple areas

DMVPN - Phase 2 BGP peerings

DMVPN - Phase 2 EIGRP neighbor adjacencies

DMVPN - Phase 2 OSPF neighbor adjacencies

DMVPN - Phase 2 and multicast traffic

DMVPN - Phase 2 and summarization

DMVPN - Using the GRE tunnel key

DMVPN - What is the best routing protocol to use

DMVPN - mappings on hub and spokes

DMVPN - multicast commands

DMVPN - nhrp map and nhs command syntax

DMVPN - spoke redundancy

DMVPN - using a default route

DMVPN State of a tunnel

DMVPN dual hub dual cloud

DMVPN dual hub single cloud

DMVPN hierarchical topology

DMVPN redundancy options

DMVPN with more than two hubs

DMVPN

DNS - Authoritative Flag

DNS - Authoritative Server

DNS - Caching

DNS - Recursive Resolver

DNS - What is a delegation zone

DNS - stub zone

DNS - understanding zones

DNS cache windows PC

DSL - Asymmetric Digital Subscriber Line (ADSL)

DTP - best practice to disable

DTP - how to disable

Decrypt IPSec ESP traffic with Wireshark

Demarcation point

Difference between per-prefix LFA and per-link based LFA

Differences between CCIE and CCDE lab exams

Diffserv recommended configuration

Distribute-lists - using route maps to set attributes

Distribute-lists and named extended ACLs

EEM - action mail

EEM Cisco Embedded Event Manager

EEM Matching a string within CLI output

EEM sync and skip keywords

EIGRP - Advertised metric is cumulative

EIGRP - Advertising a route using the network command

EIGRP - Hello interval and Hold time

EIGRP - Hop Count

EIGRP - Network command syntax

EIGRP - Queries

EIGRP - Reliable Multicast

EIGRP - Source of values for metric calculation

EIGRP - Summarization per interface

EIGRP - Update message exchange process

EIGRP - af-interface configuration mode

EIGRP - how metrics are sent in updates

EIGRP - metric computation method

EIGRP - metric equation

EIGRP - network command with no wildcard mask

EIGRP - stub site function

EIGRP Create and advertise a default route

EIGRP Feasibility condition

EIGRP Header

EIGRP IP bandwidth-percent example

EIGRP LFA FRR

EIGRP Refining the behavior of load balancing with traffic-share

EIGRP SIA timers

EIGRP authentication

EIGRP auto-summary

EIGRP change rib scale

EIGRP establishing remote neighbors

EIGRP header - ACK field

EIGRP named mode

EIGRP on the Nexus Platform

EIGRP redistributing named mode

EIGRP rib-scale

EIGRP seed metrics when redistributing

EIGRP split horizon verification

EIGRP split-horizon vs poison reverse