Enterasys IRM2, User Manual

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7-1
Chapter 7
Redundancy
Accessing the redundancy window; establishing a redundant circuit; activating the circuit; testing the
circuits; reconfiguring a circuit; changing port status; resetting a circuit
The redundancy application allows you to establish redundant circuits on the
IRM2’s repeater segment to ensure that vital network connections do not fail.
Once configured and enabled, a redundant circuit ensures that, in addition to a
primary network link to a port in the IRM2 managed-hub, there are several
backup links that will automatically assume operation should the primary (or
subsequent backup) link fail.
The IRM2 monitors the link status of the primary port for each redundant circuit
by polling the physical addresses of designated nodes on the circuit using an
Enterasys proprietary poll. Should all addresses fail to respond to the poll, a
backup link will take effect. This reduces the risk of total network failure because
of one faulty link.
Accessing the Redundancy Window
To open the Redundancy window:
1. Click on View on the Chassis View menu bar.
2. Drag down to Redundancy, and release.
Two things will occur when you select the Redundancy View: the Redundancy
Configuration window,
Figure 7-1 , will appear; and the Chassis View will change
significantly, as illustrated in Figure 7-2 . You will use these two windows in
tandem to configure your redundant circuits.
!
CAUTION
Before you configure redundancy, make sure that only the primary links are physically
connected to the network. If you have all your backup ports physically connected before
redundancy is configured and enabled, you will create multiple data loops on your
network.