OmniSwitch AOS Release 8 Network Configuration Guide December 2017 page 2-1
2 Configuring UDLD
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,
and so on. The UDLD protocol operates at Layer 2 in conjunction with the IEEE 802.3 - 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 or not
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 protocol 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 AOS Release 8 CLI Reference Guide.
Configuration procedures described in this chapter include the following:
• “Configuring UDLD” on page 2-6.
• “Configuring the Operational Mode” on page 2-7.
• “Configuring the Probe-Timer” on page 2-7.
• “Configuring the Echo-Wait-Timer” on page 2-7.
• “Clearing UDLD Statistics” on page 2-8.
• “Verifying the UDLD Configuration” on page 2-8.
• “Verifying the UDLD Configuration” on page 2-8.