Planning Considerations; Powering Considerations; Cabling Considerations - Cisco Catalyst 3750 Hardware Installation Manual

Chapter 2 Switch Installation

Planning Considerations

Before connecting the Catalyst 3750 switches in a stack, observe these planning considerations:
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Powering Considerations

Consider the following guidelines before you power the switches in a stack:
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For conditions that can cause a stack master re-election or to manually elect the stack master, see the
Note
"Managing Switch Stacks" chapter in the switch software configuration guide.

Cabling Considerations

The illustrations in this section display cabling configuration examples that show the stack bandwidth
and possible stack partitioning.
Figure 2-1
redundant StackWise cable connections.
OL-6336-06
Size of the switch. For switch dimensions, see
switches are deeper than the other switches. Stacking together switches of the same size will make
it easier to cable the switches.
Length of cable. Depending on the configurations you have, you might need different sized cables.
If you don't specify the length of the StackWise cable, the 0.5-meter cable is supplied. If you require
the 1-meter cable or 3-meter cable, you can order it from your Cisco supplier. For cable numbers,
see the "StackWise Ports" section on page
section on page 2-10 provides examples of recommended configurations.
Access to the rear ports for unrestricted cabling.
Make sure that there is access to the rear of the rack if you are planning to stack the switches. If you
do not have access to the rear panel, make sure you cable the switches before you rack-mount them.
For concepts and procedures to manage switch stacks, see the switch software configuration guide.
The sequence in which the switches are initially powered on might affect the switch that becomes
the stack master.
If you want a particular switch to become the stack master, power on that switch first. This switch
becomes the stack master and remains the stack master until a master re-election is required. After
approximately 10 seconds power on the remaining switches in the stack.
If you have no preference as to which switch becomes the stack master, power on all the switches
in the stack within a 10-second timeframe. These switches participate in the stack master election.
Switches powered on after the 10-second timeframe do not participate in the election.
Power off a switch before you add it to or remove it from an existing switch stack.
shows an example of a stack of Catalyst 3750 switches that provides full bandwidth and
Appendix A, "Technical Specifications."
1-25. The "Recommended Cabling Configurations"
Catalyst 3750 Switch Hardware Installation Guide
Planning the Stack
Some
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