About Private Vlans - Cisco Catalyst 4500 Series Configuration Manual

Configuring Private VLANs
This chapter describes how to implement private VLANs (PVLANs) on Catalyst 4500 series switches.
It also provides restrictions, procedures, and configuration examples.
This chapter includes the following major sections:
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Note For complete syntax and usage information for the switch commands used in this chapter, first look at
the Cisco Catalyst 4500 Series Switch Command Reference and related publications at this location:
http://www.cisco.com/en/US/products//hw/switches/ps4324/index.html
If the command is not found in the Catalyst 4500 Series Switch Command Reference, it will be found in
the larger Cisco IOS library. Refer to the Cisco IOS Command Reference and related publications at this
location:
http://www.cisco.com/en/US/products/ps6350/index.html

About Private VLANs

The private VLAN (PVLAN) feature addresses two problems that service providers face when using
VLANs:
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To configure PVLANs, you need to understand the concepts in these sections:
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OL-25340-01
About Private VLANs, page 42-1
PVLAN Commands, page 42-10
Configuring PVLANs, page 42-11
The switch supports up to 4094 active VLANs. If a service provider assigns one VLAN per
customer, this limits the numbers of customers the service provider can support.
To enable IP routing, each VLAN is assigned a subnet address space or a block of addresses, which
can result in wasting the unused IP addresses, and cause IP address management problems.
Purpose of a PVLAN, page 42-2
PVLAN Terminology, page 42-3
PVLANs across Multiple Switches, page 42-5
PVLAN Modes Over Gigabit Etherchannel, page 42-8
C H A P T E R
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
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