Limitations - Cisco Catalyst 3550 series Software Configuration Manual

Understanding Optional Spanning-Tree Features

Limitations

These limitations apply to CSUF:
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Connecting the Stack Ports
A fast transition occurs across the stack of switches if the multidrop backbone connections are a
continuous link from one GigaStack GBIC to another as shown in the top half of
half of
You should follow these guidelines:
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Catalyst 3550 Multilayer Switch Software Configuration Guide
18-8
CSUF uses the GigaStack GBIC and runs on all Catalyst 3550 switches, all Catalyst 3500 XL
switches, Catalyst 2950 switches with GBIC module slots, and only on modular Catalyst 2900 XL
switches that have the 1000BASE-X module installed.
Up to nine stack switches can be connected through their stack ports to the multidrop backbone.
Only one stack port per switch is supported.
Each stack switch can be connected to the spanning-tree backbone through one uplink.
If the stack consists of a mixture of Catalyst 3550, Catalyst 3500 XL, Catalyst 2950, and
Catalyst 2900 XL switches, up to 64 VLANs with spanning tree enabled are supported. If the stack
consists of only Catalyst 3550 switches, up to 128 VLANs with spanning tree enabled are
supported.
Figure 18-6 shows how to connect the GigaStack GBIC to achieve a normal convergence time.
A switch supports only one stack port.
Do not connect alternate stack-root ports to stack ports.
Connect all stack ports on the switch stack to the multidrop backbone.
You can connect the open ports on the top and bottom GigaStack GBICs within the same stack to
form a redundant link.
Chapter 18 Configuring Optional Spanning-Tree Features
Figure 18-6. The bottom
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