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GARP VLAN Registration Protocol (GVRP)
Dell Networking OS supports GARP VLAN registration protocol (GVRP).
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.
● On the Switch, you cannot enable per-VLAN spanning tree+ (PVST+) and GVRP at the same time. If spanning tree and
GVRP are both required, implement either rapid spanning tree protocol (RSTP), spanning tree protocol (STP), or multiple
spanning tree protocol (MSTP). Dell Networking OS does support enabling GVRP and MSTP at the same time.
Dell(conf)#protocol spanning-tree pvst
Dell(conf-pvst)#no disable
% Error: GVRP running. Cannot enable PVST.
.........
Dell(conf)#protocol spanning-tree mstp
Dell(conf-mstp)#no disable
% Error: GVRP running. Cannot enable MSTP.
Topics:
• Configure GVRP
• Enabling GVRP Globally
• Enabling GVRP on a Layer 2 Interface
• Configure GVRP Registration
• Configure a GARP Timer
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 exchanged. In
the following example, that type of port is referred to as a VLAN trunk port, but it is not necessary to specifically identify to the
Dell Networking operating system (OS) that the port is a trunk port.
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