Cisco Catalyst 2960 Series, Configuration Manual

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C H A P T E R
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Configuring VLAN Trunks
• Finding Feature Information, page 2129
• Prerequisites for VLAN Trunks, page 2129
• Information About VLAN Trunks, page 2130
• How to Configure VLAN Trunks, page 2133
• Configuration Examples for VLAN Trunking, page 2148
• Where to Go Next, page 2149
• Additional References, page 2149
• Feature History and Information for VLAN Trunks, page 2150
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and
feature information, see Bug Search Tool and the release notes for your platform and software release. To
find information about the features documented in this module, and to see a list of the releases in which each
feature is supported, see the feature information table at the end of this module.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to
http://www.cisco.com/go/cfn . An account on Cisco.com is not
required.
Prerequisites for VLAN Trunks
The IEEE 802.1Q trunks impose these limitations on the trunking strategy for a network:
• In a network of Cisco switches connected through IEEE 802.1Q trunks, the switches maintain one
spanning-tree instance for each VLAN allowed on the trunks. Non-Cisco devices might support one
spanning-tree instance for all VLANs.
When you connect a Cisco switch to a non-Cisco device through an IEEE 802.1Q trunk, the Cisco switch
combines the spanning-tree instance of the VLAN of the trunk with the spanning-tree instance of the
non-Cisco IEEE 802.1Q switch. However, spanning-tree information for each VLAN is maintained by
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
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