GVRP

Introduction

GVRP and VLAN Access Control

When you enable GVRP on a switch, the default GVRP parameter settings allow all of the switch’s ports to transmit and receive dynamic VLAN advertisements (GVRP advertisements) and to dynamically join VLANs. The two preceding sections describe the per-port features you can use to control and limit VLAN propagation. To summarize, you can:

Allow a port to advertise and/or join dynamic VLANs (Learn mode—the default).

Allow a port to send VLAN advertisements, but not receive them from other devices; that is, the port cannot dynamically join a VLAN but other devices can dynamically join the VLANs it advertises (Block mode).

Prevent a port from participating in GVRP operation (Disable mode).

Port-Leave From a Dynamic VLAN

A dynamic VLAN continues to exist on a port for as long as the port continues to receive advertisements of that VLAN from another device connected to that port or until you:

Convert the VLAN to a static VLAN (See “Converting a Dynamic VLAN to a Static VLAN” on page 2-26.)

Reconfigure the port to Block or Disable

Disable GVRP

Reboot the switch

The time-to-live for dynamic VLANs is 10 seconds. That is, if a port has not received an advertisement for an existing dynamic VLAN during the last 10 seconds, the port removes itself from that dynamic VLAN.

Planning for GVRP Operation

These steps outline the procedure for setting up dynamic VLANs for a seg- ment.

1.Determine the VLAN topology you want for each segment (broadcast domain) on your network.

2.Determine the VLANs that must be static and the VLANs that can be dynamically propagated.

3.Determine the device or devices on which you must manually create static VLANs in order to propagate VLANs throughout the segment.

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