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GARP VLAN Registration Protocol (GVRP)
GARP VLAN registration protocol (GVRP) is supported on the MXL switch 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.
• On the MXL 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). The MXL 10/40GbE Switch
IO Module system 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.
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