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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 14 Configuring VLA Ns Unde rst an din g VLA Ns

VLAN Port Membership Modes

You configure a port to belong to a VLAN by assigning a membership mode that determines the kind of
traf fic the port c arries and t he number of V LANs to which i t can belon g. Table 14-1 lists the membership
modes and membership and VTP characteristics.
For more det aile d definitions of the m od es an d thei r fu nc tio ns, se e Tabl e 14-4 on pa ge 14-16 .
When a port belongs to a VLAN , the switch l earns and mana ges the add resses assoc iated wit h the port
on a pe r-VLAN basis . For m or e i nforma ti on, se e t he “M anaging th e MAC Address Table” section on
page 7-54.
Table 14-1 Port Membership Modes
Membership Mode VLAN Membership Characteristics VTP Characteristics
Static- access A static -acce ss port can belo ng to one VLAN an d is
manually assigned to that VLAN. For more information,
see the “Assigning Static-Access Ports to a VL AN”
sectio n on page 14-11.
VTP i s n ot r equ ired. I f y ou do no t wan t
VTP to gl oball y propag ate inf ormati on, set
the VTP mode to transparent to disable
VTP. To participate in VTP, there must be
at le ast one tr unk po rt o n th e swit ch
connec te d to a t ru nk por t of a sec ond
switch.
802.1Q tr unk A t runk p ort i s a m embe r of a ll VLA Ns by defau lt,
including e xtended-range VLANs, b ut membership can be
limited by configuring the allowed-VLAN list. You can
also mo dify the prun ing-eli gible lis t to block flood ed
traffic to VLA Ns on tr unk ports th at ar e inc luded in the
list. For information about configuring trunk ports, see the
“Configuring an Eth ernet In terface as a Trunk Port”
sectio n on page 14-17.
VTP is recommended but not required.
VTP maintains VLAN configuration
consist ency by m an ag ing th e ad di tion,
deletio n, and re naming of VLANs on a
network-w ide b asis. VT P exch an ges
VLAN co nfiguration messa ges with othe r
switches over trunk links.
Dynamic access A dynamic-access port can belong to one normal-range
VLAN (VLAN ID 1 to 1005) and is dynamically assigned
by a VMPS. The VMPS can be a Catalyst 5000 or
Catalyst 6000 series switch, for example, but never a
Catalyst 2950 switch.
You can have dynamic-access ports and trunk ports on the
same switc h, but you mu st c onn ect t he dynam ic-a ccess
port to an e nd station and not to another switch.
For configuration information, see the “Configuring
Dynamic Access Ports on VMPS Clients” section on
page 14-29.
VTP is required.
Configure t he VMPS a nd the clie nt with
the same VTP dom ain name .
You can change the reco nfirmatio n interval
and retry count on the VMPS client sw itch.