NEC INTELLIGENT L2 SWITCH N8406-022A - Manual (Page 85)

High availability 85
High availability
Introduction
Switches support high availability network topologies. This release provides information about Uplink
Failure Detection.
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 10 Uplink Failure Detection for switches
CPU Blade
1 2
NIC
Layer2/3
Switch
Layer2/3
Switch
CPU Blade
1 2
NIC
CPU Blade
1 2
NIC
GbE
Intelligent
Switch 1
GbE
Intelligent
Switch 2
LtD LtD
LtM LtM
Failure Detection Pair Failure Detection Pair
NOTE: The port numbers specified in these illustrations may not directly correspond to the physical port
configuration of your system.
Blade Enclosure