Handbook

N8406-023 1Gb Intelligent L3 Switch Application Guide 142
High availability
Introduction
Switches support high availability network topologies. This release provides information about Uplink
Failure Detection and Virtual Router Redundancy Protocol (VRRP).
Uplink Failure Detection
Uplink Failure Detection (UFD) is designed to support Network Adapter Teaming on the CPU Blades.
UFD allows the switch to monitor specific uplink ports to detect link failures. When the switch detects a link failure, it
automatically disables specific downlink ports. The corresponding server‘s network adapter can detect the disabled
downlink, and trigger a network-adapter failover to another port on the switch, or another switch in the chassis.
The switch automatically enables the downlink ports when the uplink returns to service.
The following figure shows a basic UFD configuration, with a Failure Detection Pair (FDP) that consists of one LtM
(Link to Monitor) and one LtD (Link to Disable). When the switch detects a link failure in the LtM, it disables the
ports in the LtD. The server blade detects the disabled downlink port, which triggers a NIC failover.
Figure 23 Uplink Failure Detection for switches
NOTE: The port numbers specified in these illustrations may not directly correspond to the physical port
configuration of your system.
Blade Enclosure