Enterasys Enterasys Matrix DFE-Gold Series, Configuration Manual

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Enabling/Disabling GVRP set vlan dynamicegress
7-22 802.1Q VLAN Configuration
Enabling/Disabling GVRP
Purpose
To dynamically create VLANs across a switched network. The GVRP (GARP VLAN Registration
Protocol) command set is used to display GVRP configuration information, the current global
GVRP state setting, individual port settings (enable or disable) and timer settings. By default,
GVRP is enabled on all ports, and globally on the device.
GARP VLAN Registration Protocol (GVRP) Operation
The following sections describe the device operation when its ports are operating under the
Generic Attribute Registration Protocol (GARP) application – GARP VLAN Registration Protocol
(GVRP).
Overview
The purpose of GVRP is to dynamically create VLANs across a switched network. When a VLAN
is declared, the information is transmitted out GVRP configured ports on the device in a GARP
formatted frame using the GVRP multicast MAC address. A switch/router that receives this frame,
examines the frame, and extracts the VLAN IDs. GVRP then creates the VLANs and adds the
receiving port to its tagged member list for the extracted VLAN ID (s). The information is then
transmitted out the other GVRP configured ports of the device. Figure 7 ‐ 1 shows an example of
how VLAN blue from end station A would be propagated across a switch/router network.
How It Works
In Figure 7 ‐ 1 , Device 4, port 1 is registered as being a member of VLAN Blue and then declares
this fact out all its ports (2 and 3) to Device 1 and Device 2. These two devices register this in the
port egress lists of the ports (Device 1, port 1 and Device 2, port 1) that received the frames with
the information. Device 2, which is connected to Device 3 and Device 5 declares the same
information to those two devices and the port egress list of each port is updated with the new
information, accordingly.