Reference Guide

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GARP VLAN Registration Protocol (GVRP)
GARP VLAN registration protocol (GVRP) is supported on the Z9000 platform.
Typical virtual local area network (VLAN) implementation involves manually configuring each Layer 2 switch that
participates in a given VLAN. GVRP, defined by the IEEE 802.1q specification, is a Layer 2 network protocol that provides
for automatic VLAN configuration of switches. GVRP-compliant switches use GARP to register and de-register attribute
values, such as VLAN IDs, with each other.
GVRP exchanges network VLAN information to allow switches to dynamically forward frames for one or more VLANs.
Therefore, GVRP spreads this information and configures the needed VLANs on any additional switches in the network.
Data propagates via the exchange of GVRP protocol data units (PDUs).
The purpose of GVRP is to simplify (but not eliminate) static configuration. The idea is to configure switches at the edge
and have the information dynamically propagate into the core. As such, the edge ports must still be statically configured
with VLAN membership information, and they do not run GVRP. It is this information that is propagated to create dynamic
VLAN membership in the core of the network.
Important Points to Remember
• GVRP propagates VLAN membership throughout a network. GVRP allows end stations and switches to issue and
revoke declarations relating to VLAN membership.
• VLAN registration is made in the context of the port that receives the GARP PDU and is propagated to the other
active ports.
• GVRP is disabled by default; enable GVRP for the switch and then for individual ports.
• Dynamic VLANs are aged out after the LeaveAll timer expires three times without receipt of a Join message. To
display status, use the show gvrp statistics {interface interface | summary} command.
FTOS(conf)#protocol spanning-tree pvst
FTOS(conf-pvst)#no disable
% Error: GVRP running. Cannot enable PVST.
.........
FTOS(conf)#protocol spanning-tree mstp
FTOS(conf-mstp)#no disable
% Error: GVRP running. Cannot enable MSTP.
.........
FTOS(conf)#protocol gvrp
FTOS(conf-gvrp)#no disable
% Error: PVST running. Cannot enable GVRP.
% Error: MSTP running. Cannot enable GVRP.
Configure GVRP
To begin, enable GVRP.
To facilitate GVRP communications, enable GVRP globally on each switch. Then, GVRP configuration is per interface on
a switch-by-switch basis. Enable GVRP on each port that connects to a switch where you want GVRP information
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