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Cabling a Catalyst Stack Configuration
Catalyst 3920 Token Ring Switch User Guide
3-6
Step 4
Label this cable.
Step 5
Continue with the instructions in the “Powering On the Catalyst 3920” section.
Cabling a Catalyst Stack Configuration
As an option, you can configure your Catalyst 3920 as a part of a Catalyst stack. There are two
Catalyst stack configurations.
•
Two Catalyst 3920 switches cabled together to form a back-to-back stack
•
Up to eight Catalyst 3920 switches cabled together using a Catalyst Matrix
The next two sections describe how to cable the Catalyst stack equipment. The first section explains
connecting two Catalyst switches back-to-back. The second section describes how to connect
Catalyst switches to the Catalyst Matrix.
Note
The software levels of all Catalysts in a stack should be the same. Therefore, downloading
new software (such as updating firmware levels) to a single Catalyst 3920 while it is part of a stack
will cause conflicts within the stack. If you need to download new software to the Catalyst 3920, we
recommend that you either download the software to all the switches in the stack at one time or that
you disconnect the switches, update them individually, and then reconnect them to the stack.
Note
Before you create a stack, or add to a stack, if any of the Catalyst 3920 units need software
downloaded, download the software before cabling the Catalyst 3920 units together.
Catalyst Stack Back-to-Back Connection
Keep the following in mind when you install two Catalyst switches in a back-to-back configuration.
1
One stack port cable is used to connect to the I/O stack port on each switch.
2
The stack port cable can be connected or disconnected, when power to either Catalyst switch is
on or off.
3
To prevent bending the pins, do not install the stack port cable connector at an angle. Use care
when inserting the cable connector straight into the stack port connector.
To install two Catalyst switches in a back-to-back configuration, follow these steps:
Step 1
Connect one end of the stack port cable to the stack port on one Catalyst switch. It does
not matter which end of the cable is used. Either end of the stack port cable can be
connected to either one of the Catalyst switches.
Step 2
Connect the other end of the cable to the stack port on the other Catalyst switch.
Figure 3-4 and Figure 3-5 show how two Catalyst switches are cabled together (the cable connector
is shown at an angle for illustration purposes only).