Confidential and proprietary information of Extreme Networks. © 2011 Extreme Networks, Inc.
All rights reserved. DRAFT. October 20, 2011
Summit Family Switches Hardware Installation Guide
153
About Redundancy
When your stack is operational, one switch is the primary (or master) switch that is responsible for
running network protocols and managing the stack. To provide recovery in case of a break in the stack
connections, you can configure redundancy by designating a backup switch to take over as master if the
master switch fails. When you perform the initial software configuration of the stack, the “easy setup”
configuration option automatically configures redundancy, with slot 1 as the master and slot 2 as the
backup. You can also configure additional switches as “master-capable” to become a stack master in
case the initial backup switch fails.
In a stack that combines Summit X460, X480, or X650 series switches with other Summit switch models,
a Summit X460, X480, or X650 series switch might provide more memory and more features than other
Summit switch models in the stack. These differences can affect master node selection, backup node
selection, and failover operation. The master and backup roles should be assigned to switches from the
same series. For example, if the master node is a Summit X480 series switch, the backup node should
also be a Summit X480 switch. Similarly, if the master node is a Summit X650 series switch, the backup
node should also be a Summit X650 switch.
The choice of which switches should be the master and backup switches is based on a combination of
the feature scalability of each switch, along with the switch speed.
Table 49
shows the hierarchy of these
qualities for the different switch models and can help you plan the physical placement of the switches
in the stack.
Combining Switches from Different Series
In a stack that has switch models from more than one Summit series, refer to
Table 49
and follow these
guidelines:
●
The stack master and backup nodes should be from the same switch series. For example, if a
Summit X480 series switch is the stack master, the backup node should also be a Summit X480 series
switch.
●
If the
scalability
is the same for all switches in the stack, use models with higher speed as the stack
master and backup.
●
If the
speed
is the same for all switches in the stack, use models with higher scalability as the stack
master and backup.
●
Always choose the switches with the highest scalability as the stack master and backup, even if those
particular switches have lower speed ratings. For example:
-
If Summit X480 series and X650 series switches are both present in the stack, the master and
backup nodes should both be Summit X480 series switches.
-
If Summit X480 series and X460 series switches are both present in the stack, the master and
backup nodes should both be Summit X480 series switches.
Table 49: Scalability and Speed Comparison for Summit Switch Series
Speed
------>
Higher
Higher
X480
X670
X460
X650
X450a
X250e
X450e
Lower
X150
X350
S
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a
la
b
il
it
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