Configuring Vlan Trunks; Finding Feature Information; Prerequisites For Vlan Trunks - Cisco Catalyst 2960 series Configuration Manual

Configuring VLAN Trunks

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Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature
information and caveats, see the release notes for your platform and software release.
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
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Finding Feature Information, page 59
Prerequisites for VLAN Trunks, page 59
Information About VLAN Trunks, page 60
How to Configure VLAN Trunks, page 64
Configuration Examples for VLAN Trunking, page 78
Where to Go Next, page 79
Additional References, page 79
Feature History and Information for VLAN Trunks, page 80
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
Cisco switches separated by a cloud of non-Cisco IEEE 802.1Q switches. The non-Cisco IEEE 802.1Q
cloud separating the Cisco switches is treated as a single trunk link between the switches.
Catalyst 2960-X Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX
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