Chapter 17 Configuring Udld; In This Chapter - Alcatel-Lucent OmniSwitch 6850-48 Network Configuration Manual

UniDirectional Link Detection (UDLD) is a protocol for detecting and disabling unidirectional Ethernet
fiber or copper links caused by mis-wiring of fiber strands, interface malfunctions, media converter faults,
etc. The UDLD operates at Layer 2 in conjunction with IEEE 802.3's existing Layer 1 fault detection
mechanisms.
UDLD is a lightweight protocol that can be used to detect and disable one-way connections before they
create dangerous situations such as Spanning Tree loops or other protocol malfunctions. The protocol is
mainly used to advertise the identities of all the UDLD-capable devices attached to the same LAN
segment and to collect the information received on the ports of each device to determine whether the Layer
2 communication is functioning properly. All connected devices must support UDLD for the protocol to
successfully identify and disable unidirectional links. When UDLD detects a unidirectional link, the proto-
col administratively shuts down the affected port and generates a trap to alert the user.

In This Chapter

This chapter describes how to configure UDLD parameters through the Command Line Interface (CLI).
CLI commands are used in the configuration examples; for more details about the syntax of commands,
see the OmniSwitch CLI Reference Guide.
Configuration procedures described in this chapter include the following:
•
Configuring UDLD on
•
Configuring the operational mode on
•
Configuring the probe-message advertisement timer on
•
Configuring the echo-based detection timer on
•
Clearing UDLD statistics on
•
Recovering a port from UDLD shutdown on
•
Verifying the UDLD Configuration on
OmniSwitch AOS Release 6 Network Configuration Guide
17 Configuring UDLD
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