Guidelines For Interconnecting Units - 3Com 3CR17561-91-US - Switch 4500 26PORT Managed 24 10/100 2 Gbe Stackable RJ45 Getting Started Manual

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HAPTER REATING A
Guidelines For
Interconnecting
Units
S
TACK
As with all Switch 4500 CLI commands, the format for entering a port-
specific command is x/y/z, where x = unit number, y = module number (in
the case of the Switch 4500 this will always be 0), z = port number.
3 Connect the stack-enabled 'up' port on one Switch 4500 unit to the
stack-enabled 'down' port on another Switch 4500 unit using the
appropriate connection method for your Switch.
4 Save all configuration settings. From the User View, enter the save
command to save the configuration to your Switch.
This section offers some guidelines for creating a stack. Using these
guidelines will help prevent problems arising when setting up your stack.
The 3Com Switch 4500 supports stacking by daisy-chaining from unit to
unit over standard Gigabit Ethernet connections. Resilient stacking, with
a return loop from bottom to top of a stack, is not supported and will
disable stack operation.
The maximum number of Switch units that can be interconnected is
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eight.
You can only create a stack by interconnecting a 3Com Switch 4500
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with other 3Com Switch 4500s.
Stacking is only supported using Gigabit ports.
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The stacking connections must be from one combo port pair on a unit
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to the opposite combo port pair on the next unit. Refer to Figure 22 to
see how this looks in a stack of units.
The stacking ports must be configured for "fabric mode" before they
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can be used for stacking. By default, fabric mode is enabled for ports
25/26 and 49/50. The configuration can be changed to move fabric
mode to the other port pair; this requires a reboot of the system.
3Com strongly recommends that you upgrade all Switches to be
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interconnected to the latest software agent.
3Com recommends that you remove the configuration file from a
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Switch unit that has previously been used elsewhere in your network
before you interconnect to an existing unit. If you do not do this,
problems may be caused by conflicting Switch configurations. Use the
dir command from the User View to display the configuration files
stored on the Switch and locate the [filename].cfg file. Do NOT
under any circumstances remove the 3comoscfg.def file (this is the
default configuration file).