About Redundancy; Placing Summit Family Switches For Stacked Operation; Connecting The Switches To Form The Stack Ring - Extreme Networks Summit X150 Series Installation Manual

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 with multiple master-capable switches, it is possible for more than one switch to try become
the stack master if the stack is physically severed. Such a dual-master condition would cause confusion
and loss of connectivity in your networks. To resolve a dual-master condition, you must be able to log
in to each severed stack segment, either over the management network (using the Ethernet management
port on a switch in the segment) or through a direct console port connection to each switch in the
segment.
Stack configuration, easy setup, and redundancy are fully described in the ExtremeXOS 12.0 Concepts
Guide.

Placing Summit Family Switches for Stacked Operation

This section summarizes the recommended best practices for installing Summit switches for a
SummitStack configuration. For detailed information about how to configure and manage the stack and
how a stack operates, refer to the ExtremeXOS 12.0 Concepts Guide.
When you install switches for a SummitStack configuration, follow these recommendations:
Use the shortest possible stacking cables to connect the switches in the stack; this reduces the
●
likelihood that the stacking cables might be accidentally damaged or disconnected. Stacking cables
are available in lengths from 0.3 meters to 5 meters (see
When possible, place all switches for the stack in the same rack; this facilitates using shorter stacking
●
cables.
Because the switches will form a ring, make sure that no two switches in the stack are located more
●
than 5 meters apart.
For simplicity and ease of connecting the stacking cables, plan to designate the top switch in the
●
physical stack as the stack master. This is the switch through which you will perform the initial stack
configuration, using the console port.
Connect the stacking cables in the order and arrangement shown in
●
On the stack master switch, connect the Ethernet management port to your management network.
●
To provide management access to the stack in case of a failure in the master switch, connect all
●
switches that will participate in redundancy to your management network using the Ethernet
management port on each switch.

Connecting the Switches to Form the Stack Ring

After you have installed the individual Summit switches, connect the switches together using the
stacking cables. Table 18
two sample configurations;
connect them in any order, connecting the switches as shown in these examples will produce better
predictability and easier software configuration. Connect Stack Port 2 on one switch to Stack Port 1 on
the switch with the next higher slot number.
ExtremeXOS Summit Family Switches Hardware Installation Guide
and Table 19 list the recommended order for connecting the stacking ports in
Figure 59 and Figure 60
Table 17).
Table 18
show the cable connections. Although you can
and Table 19.
89