Chapter 13 Configuring Vlan; Supported Vlans; Vlan Port Membership Modes - Cisco WS-C3750-48PS-S Software Configuration Manual

Chapter 13 Configuring VLANs

Supported VLANs

The switch supports 1005 VLANs in VTP client, server, and transparent modes. VLANs are identified
with a number from 1 to 4094. VLAN IDs 1002 through 1005 are reserved for Token Ring and FDDI
VLANs. VTP only learns normal-range VLANs, with VLAN IDs 1 to 1005; VLAN IDs greater than
1005 are extended-range VLANs and are not stored in the VLAN database. The switch must be in VTP
transparent mode when you create VLAN IDs from 1006 to 4094.
Although the switch stack supports a total of 1005 (normal-range and extended-range) VLANs, the
number of routed ports, SVIs, and other configured features affects the use of the switch hardware.
The switch supports per-VLAN spanning-tree plus (PVST+) or rapid PVST+ with a maximum of 128
spanning-tree instances. One spanning-tree instance is allowed per VLAN. See the
VLAN Configuration Guidelines" section on page 13-6
spanning-tree instances and the number of VLANs. The switch supports both Inter-Switch Link (ISL)
and IEEE 802.1Q trunking methods for sending VLAN traffic over Ethernet ports.

VLAN Port Membership Modes

You configure a port to belong to a VLAN by assigning a membership mode that specifies the kind of
traffic the port carries and the number of VLANs to which it can belong.
modes and membership and VTP characteristics.
Table 13-1 Port Membership Modes
Membership Mode VLAN Membership Characteristics
Static-access A static-access port can belong to one VLAN and is
manually assigned to that VLAN.
For more information, see the
Ports to a VLAN" section on page
Trunk (ISL or A trunk port is a member of all VLANs by default,
IEEE 802.1Q) including extended-range VLANs, but membership can be
limited by configuring the allowed-VLAN list. You can
also modify the pruning-eligible list to block flooded
traffic to VLANs on trunk ports that are included in the
list.
For information about configuring trunk ports, see the
"Configuring an Ethernet Interface as a Trunk Port"
section on page
78-16180-02
"Assigning Static-Access
13-11.
13-19.
for more information about the number of
Table 13-1
VTP Characteristics
VTP is not required. If you do not want
VTP to globally propagate information, set
the VTP mode to transparent. To
participate in VTP, there must be at least
one trunk port on the switch stack
connected to a trunk port of a second
switch or switch stack.
VTP is recommended but not required.
VTP maintains VLAN configuration
consistency by managing the addition,
deletion, and renaming of VLANs on a
network-wide basis. VTP exchanges
VLAN configuration messages with other
switches over trunk links.
Catalyst 3750 Switch Software Configuration Guide
Understanding VLANs
"Normal-Range
lists the membership
13-3