Configuring Uplink Failure Detection; Understanding Uplink Failure Detection; Uplink Failure Detection Overview - Juniper EX9200 Features Manual

CHAPTER 3

Configuring Uplink Failure Detection

Understanding Uplink Failure Detection

Uplink Failure Detection Overview

Copyright © 2016, Juniper Networks, Inc.
Understanding Uplink Failure Detection on page 33
Configuring Interfaces for Uplink Failure Detection (CLI Procedure) on page 35
Uplink failure detection allows Juniper Networks EX Series Ethernet Switches to detect
link failure on uplink interfaces and to propagate the failure to the downlink interfaces
so that servers connected to those downlink interfaces can switch over to secondary
interfaces.
Uplink failure detection supports network adapter teaming and provides network
redundancy. In network adapter teaming, all the network interface cards (NICs) on a
server are configured in a primary or secondary relationship and share the same IP address.
When the primary link goes down, the server transparently shifts the connection to the
secondary link. With uplink failure detection, the switch monitors uplink interfaces for
link failures. When it detects a failure, it disables the downlink interfaces. When the server
detects disabled downlink interfaces, it switches over to the secondary link to help ensure
balanced traffic flow on switches.
This topic describes:
Uplink Failure Detection Overview on page 33
Failure Detection Pair on page 34
Uplink failure detection allows switches to monitor uplink interfaces to spot link failures.
When a switch detects a link failure, it automatically disables the downlink interfaces in
that group. The server that is connected to the disabled downlink interfaces triggers a
network-adapter failover to a secondary link to avoid any information drop.
Figure 2 on page 34 illustrates a typical setup for uplink failure detection.
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