TP-Link T2500-28TCTL-SL5428E T2500-28TCUN V1 User Guide - Page 138

DLDP, Error Frame Event

Page 138 highlights

Error Frame Event: Error Frame Period Event: Error Frame Seconds Event: Dying Gasp: Critical Event:  Event Log Table Type: Location: Timestamp: Value: Window: Threshold: Accumulated Errors: Displays the number of error frame link events that have occurred on the local link or remote link. Displays the number of error frame period link events that have occurred on the local link or remote link. Displays the number of error frame seconds link events that have occurred on the local link or remote link. Displays the number of Dying Gasp link events that have occurred on the local link or remote link. Displays the number of Critical Event link events that have occurred on the local link or remote link. Displays the type of the link event. Displays the location where the link event occurred. Displays the time reference when the link event occurred. Displays the number of errors in the period. Displays the period of the link event. Displays the number of errors that is required to be exceeded in order for the event to be generated. Displays the number of errors that have been detected since the OAM sublayer was reset. 8.6 DLDP  DLDP Overview DLDP (Device Link Detection Protocol) is a Layer 2 protocol that enables devices connected through fiber or twisted-pair Ethernet cables to monitor the physical configuration of the cables and detect whether a unidirectional link exists. When a unidirectional link appears, the local device can receive packets from the peer device through the link layer, but the peer device cannot receive packets from the local device. Unidirectional links can cause a variety of problems, such as spanning-tree topology loops. Once detecting a unidirectional link, DLDP can shut down the related port automatically or inform users.  DLDP Operation Mechanism 1. DLDP Link States DLDP defines 6 link states for a device:Initial, Inactive, Active, Advertisement, Probe and Disable. State Initial Inactive Active Description DLDP is disabled. DLDP is enabled but the link is down. This state is temporary and it indicates that: 1. DLDP is enabled and the link is up. 2. The neighbor entries in this device are empty. 128

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128
Error Frame Event:
Displays the number of error frame link events that have
occurred on the local link or remote link.
Error Frame Period
Event:
Displays the number of error frame period link events that have
occurred on the local link or remote link.
Error Frame
Seconds Event:
Displays the number of error frame seconds link events that have
occurred on the local link or remote link.
Dying Gasp:
Displays the number of Dying Gasp link events that have
occurred on the local link or remote link.
Critical Event:
Displays the number of Critical Event link events that have
occurred on the local link or remote link.
Event Log Table
Type:
Displays the type of the link event.
Location:
Displays the location where the link event occurred.
Timestamp:
Displays the time reference when the link event occurred.
Value:
Displays the number of errors in the period.
Window:
Displays the period of the link event.
Threshold:
Displays the number of errors that is required to be exceeded in
order for the event to be generated.
Accumulated
Errors:
Displays the number of errors that have been detected since the
OAM sublayer was reset.
8.6 DLDP
DLDP Overview
DLDP (Device Link Detection Protocol) is a Layer 2 protocol that enables devices connected
through fiber or twisted-pair Ethernet cables to monitor the physical configuration of the cables and
detect whether a unidirectional link exists. When a unidirectional link appears, the local device can
receive packets from the peer device through the link layer, but the peer device cannot receive
packets from the local device. Unidirectional links can cause a variety of problems, such as
spanning-tree topology loops. Once detecting a unidirectional link, DLDP can shut down the
related port automatically or inform users.
DLDP Operation Mechanism
1. DLDP Link States
DLDP defines 6 link states for a device
Initial, Inactive, Active, Advertisement, Probe and Disable.
State
Description
Initial
DLDP is disabled.
Inactive
DLDP is enabled but the link is down.
Active
This state is temporary and it indicates that:
1. DLDP is enabled and the link is up.
2. The neighbor entries in this device are empty.