13-3
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-12247-04
Chapter 13 Configuring VLANs
Understanding VLANs
VLAN range (VLANs 1 to 4094). Extended range VLANs (VLANs 1006 to 4094) are supported only in
VTP version 3. You cannot convert from VTP version 3 to VTP version 2 if extended VLANs are
configured in the domain.
Although the switch or 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
for more information about the number of
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.
lists the membership
modes and membership and VTP characteristics.
Table 13-1
Port Membership Modes and Characteristics
Membership Mode
VLAN Membership Characteristics
VTP 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 13-10
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 or the switch stack connected
to a trunk port of a second switch or switch
stack.
Trunk (ISL or
IEEE 802.1Q)
A trunk port is a member of all VLANs by default,
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 13-18
.
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.
Dynamic access
A dynamic-access port can belong to one VLAN (VLAN
ID 1 to 4094) and is dynamically assigned by a VMPS.
The VMPS can be a Catalyst 5000 or Catalyst 6500
series switch, for example, but never a blade switch. The
switch is a VMPS client.
You can have dynamic-access ports and trunk ports on
the same switch, but you must connect the
dynamic-access port to an end station or hub and not to
another switch.
For configuration information, see the
Dynamic-Access Ports on VMPS Clients” section on
page 13-30
.
VTP is required.
Configure the VMPS and the client with the
same VTP domain name.
To participate in VTP, at least one trunk
port on the switch or a switch stack must be
connected to a trunk port of a second switch
or switch stack.
