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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 18 Configuring VTP
Information About Configuring VTP
If you configure a switch for VTP transparent mode, you can create and modify VLANs, but the changes
are not sent to other switches in the domain, and they affect only the individual switch. However,
configuration changes made when the switch is in this mode ar e saved in the switch running
configuration and can be saved to the switch startup configuration file.
For domain name and password configuration guidelines, see the “VTP Configuration Guidelines”
section on page 18-9.
VTP Modes

VTP Mode Guidelines

• For VTP version 1 and version 2, if extended-range VLANs are configured on the switch, you cannot
change VTP mode to client or server. You receive an error message, and the configuration is not
allowed. VTP version 1 and version 2 do not propagate configuration information for extended range
VLANs (VLANs 1006 to 4096). You must manually configure these VLANs on each device.
Tab l e 18-1 VTP Modes
VTP Mode Description
VTP server In VTP server mode, you can create, modify, and delete VLANs, and specify other configuration
parameters (such as the VTP version) for the entire VTP domain. VTP servers advertise their VLAN
configurations to other switches in the same VTP domain and synchronize their VLAN configurations with
other switches based on advertisements received over trunk links.
VTP server is the default mode.
Note In VTP server mode, VLAN configurations are saved in NVRAM. If the sw itch detects a failure
while writing a configuration to NVRAM, VTP mode automatically changes from server mode to
client mode. If this happens, the switch cannot be returned to VTP server mode until the NVRAM
is functioning.
VTP client A VTP client behaves like a VTP server and transmits and receives VTP updates on i ts trunks, but you
cannot create, change, or delete VLANs on a VTP client. VLANs are configured on another switch in the
domain that is in server mode.
In VTP versions 1 and 2, in VTP client mode, VLAN configurations are not saved in NVRAM. In VTP
version 3, VLAN configurations are saved in NVRAM in client mode.
VTP transparent VTP transparent switches do not participate in VTP. A VTP transparent switch does not advertise its VLAN
configuration and does not synchronize its VLAN configuration based on received advertisements.
However, in VTP version 2 or version 3, transparent switches do forward VTP advertisements that they
receive from other switches through their trunk interfaces. You can create, modify, and delete VLANs on
a switch in VTP transparent mode.
In VTP versions 1 and 2, the switch must be in VTP transparent mode when you create extended-range
VLANs. VTP version 3 also supports creating extended-range VLA Ns in client or server mode. See the
“Creating an Extended-Range VLAN” section on page 17-18 .
When the switch is in VTP transparent mode, the VTP and VLAN configurations are saved in NVRAM,
but they are not advertised to other switches. In this mode, VTP mode and domain name are saved in the
switch running configuration, and you can save this information in the switch start up configuration file by
using the copy running-config startup-config privileged EXEC command.
VTP off A switch in VTP off mode functions in the same manner as a VTP transparent switch, except that it does
not forward VTP advertisements on trunks.