Reference Guide

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GARP VLAN Registration (GVRP)
The Dell Networking operating system (FTOS) supports the basic GVRP commands on the S4820T platform.
The generic attribute registration protocol (GARP) mechanism allows the configuration of a GARP participant to
propagate through a network quickly. A GARP participant registers or de-registers its attributes with other participants
by making or withdrawing declarations of attributes. At the same time, based on received declarations or withdrawals,
GARP handles attributes of other participants.
GVRP enables a device to propagate local VLAN registration information to other participant devices and dynamically
update the VLAN registration information from other devices. The registration information updates local databases
regarding active VLAN members and through which port the VLANs can be reached.
GVRP ensures that all participants on a bridged LAN maintain the same VLAN registration information. The VLAN
registration information propagated by GVRP includes both manually configured local static entries and dynamic entries
from other devices.
GVRP participants have the following components:
• The GVRP application
• GARP information propagation (GIP)
• GARP information declaration (GID)
Important Points to Remember
• GVRP is supported on Layer 2 ports only.
• All VLAN ports added by GVRP are tagged.
• GVRP is supported on untagged ports belonging to a default VLAN and tagged ports.
• GVRP cannot be enabled on untagged ports belonging to a non-default VLAN unless native VLAN is turned on.
• GVRP requires end stations with dynamic access NICs.
• Based on updates from GVRP-enabled devices, GVRP allows the system to dynamically create a port-based
VLAN (unspecified) with a specific VLAN ID and a specific port.
• On a port-by-port basis, GVRP allows the system to learn about GVRP updates to an existing port-based VLAN
with that VLAN ID and IEEE 802.1Q tagging.
• GVRP allows the system to send dynamic GVRP updates about your existing port-based VLAN.
• GVRP updates are not sent to any blocked spanning tree protocol (STP) ports. GVRP operates only on ports that
are in the forwarding state.
• GVRP operates only on ports that are in the STP forwarding state. If you enable GVRP, a port that changes to the
STP Forwarding state automatically begin to participate in GVRP. A port that changes to an STP state other than
forwarding no longer participates in GVRP.
• VLANs created dynamically with GVRP exist only as long as a GVRP-enabled device is sending updates. If the
devices no longer send updates, or GVRP is disabled, or the system is rebooted, all dynamic VLANs are
removed.
• GVRP manages the active topology, not non-topological data such as VLAN protocols. If a local bridge must
classify and analyze packets by VLAN protocols, manually configure protocol-based VLANs, and simply rely on
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