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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
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Chapter 14 Configuring VTP
Configuring VTP
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When a VTP version 3 device trunk port receives messages from a VTP version 2 device, it sends a
scaled-down version of the VLAN database on that particular trunk in VTP version 2 format. A VTP
version 3 device does not send VTP version 2-formatted packets on a trunk unless it first receives
VTP version 2 packets on that trunk port.
•
When a VTP version 3 device detects a VTP version 2 device on a trunk port, it continues to send
VTP version 3 packets, in addition to VTP version 2 packets, to allow both kinds of neighbors to
coexist on the same trunk.
•
A VTP version 3 device does not accept configuration information from a VTP version 2 or version
1 device.
•
Two VTP version 3 regions can only communicate in transparent mode over a VTP version 1 or
version 2 region.
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Devices that are only VTP version 1 capable cannot interoperate with VTP version 3 devices.
Configuration Requirements
When you configure VTP, you must configure a trunk port on the switch or switch stack so that the
switch can send and receive VTP advertisements to and from other switches in the domain.
For more information, see the
“Configuring VLAN Trunks” section on page 13-15
.
In VTP versions 1 and 2, when you configure extended-range VLANs on the switch, the switch must be
in VTP transparent mode. VTP version 3 also supports creating extended-range VLANs in client or
server mode.
VTP does not support private VLANs. VTP version 3 does support private VLANs. If you configure
private VLANs when the switch is running VTP version 1 or 2, the switch must be in VTP transparent
mode. When private VLANs are configured on the switch, do not change the VTP mode from transparent
to client or server mode.
Configuring VTP Mode
You can configure VTP mode as one of these:
•
When a switch is in VTP server mode, you can change the VLAN configuration and have it
propagated throughout the network.
•
When a switch is in VTP client mode, you cannot change its VLAN configuration. The client switch
receives VTP updates from a VTP server in the VTP domain and then modifies its configuration
accordingly.
•
When you configure the switch for VTP transparent mode, VTP is disabled on the switch. The
switch does not send VTP updates and does not act on VTP updates received from other switches.
However, a VTP transparent switch running VTP version 2 does forward received VTP
advertisements on its trunk links.
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VTP off mode is the same as VTP transparent mode except that VTP advertisements are not
forwarded.