VTP CharacteristicsVLAN Membership CharacteristicsMembership Mode
VTPis recommendedbut not
required.VTP maintainsVLAN
configurationconsistency by
managingthe addition, deletion,
andrenaming of VLANson a
network-widebasis. VTP
exchangesVLAN configuration
messageswith other switches over
trunklinks.
Atrunk port is a member of all
VLANsby default,including
extended-rangeVLANs, but
membershipcan be limitedby
configuringthe allowed-VLAN
list.You can also modify the
pruning-eligiblelist to block
floodedtraffic to VLANs on trunk
portsthat are includedin the list.
Trunk(IEEE 802.1Q) :
•IEEE802.1Q—
Industry-standardtrunking
encapsulation.
VTPis required.
Configurethe VMPS and the client
withthe same VTP domainname.
Toparticipate in VTP, at least one
trunkport on the switch or a switch
stackmust be connected to a trunk
portof a second switch or switch
stack.
Adynamic-access port can belong
toone VLAN (VLAN ID 1 to
4094)and is dynamically assigned
bya VLAN Member Policy Server
(VMPS).
TheVMPS can be a Catalyst 6500
seriesswitch, for example,but
nevera Catalyst2960, 2960-S, or
2960-Cswitch. The Catalyst 2960,
2960-S,or 2960-C switch is a
VMPSclient.
Youcan have dynamic-access ports
andtrunk ports on the same switch,
butyou mustconnect the
dynamic-accessport to anend
stationor hub and not to another
switch.
Dynamicaccess
VTPis not required; it has no effect
ona voiceVLAN.
Avoice VLAN portis an access
portattached to aCisco IPPhone,
configuredto use oneVLAN for
voicetraffic and another VLAN for
datatraffic from a device attached
tothe phone.
VoiceVLAN
Normal-Range VLAN Overview
Normal-rangeVLANs are VLANs with VLAN IDs 1 to 1005. If the switch is in VTP server or VTP transparent
mode,you can add, modify or remove configurations for VLANs 2 to 1001 in the VLAN database. (VLAN
IDs1 and 1002 to 1005 are automatically created and cannot be removed.)
InVTP versions 1 and 2, the switch must be in VTP transparent mode when you create extended-range VLANs
(VLANswith IDs from 1006 to 4094), but these VLANs are not saved in the VLAN database. VTP version
3supports extended-rangeVLANs in VTP server and transparent mode.
Configurationsfor VLAN IDs 1 to 1005 are written to the file vlan.dat (VLAN database), and you can display
themby entering the show vlan privileged EXEC command. The vlan.dat file is stored in flash memory. On
Catalyst 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
42 OL-29440-01
Configuring VLANs
Normal-Range VLAN Overview