Table of Contents

Chapter 1 GVRP Configuration. 1-1

1.1 Introduction to GVRP. 1-1

1.1.1 GARP. 1-1

1.1.2 GVRP. 1-4

1.1.3 Protocols and Standards. 1-4

1.2 Configuring GVRP. 1-5

1.2.1 Configuring GVRP Functions. 1-5

1.2.2 Configuring GARP Timers. 1-5

1.3 Displaying and Maintaining GVRP. 1-7

1.4 GVRP Configuration Example. 1-7

1.4.1 GVRP Configuration Example I 1-7

1.4.2 GVRP Configuration Example II 1-8

1.4.3 GVRP Configuration Example III 1-10

 

Chapter 1  GVRP Configuration

The GARP VLAN registration protocol (GVRP) is a GARP application. Based on the operating mechanism of GARP, GVRP maintains and propagates dynamic VLAN registration information for the GVRP devices on a network.

When configuring GVRP, go to these sections for information you are interested in:

l           Introduction to GVRP

l           Configuring GVRP

l           Displaying and Maintaining GVRP

l           GVRP Configuration Example

1.1  Introduction to GVRP

This section covers these topics:

l           GARP

l           GVRP Configuration

l           Protocols and Standards

1.1.1  GARP

The generic attribute registration protocol (GARP) provides a mechanism that allows GARP participants in a LAN to distribute, propagate, and register with other participants some attributes such as VLAN IDs or multicast addresses.

GARP itself does not exist on a device as an entity. GARP-compliant application entities are called GARP applications. One example is GVRP. When a GARP application entity is present on a port on your device, this port is regarded a GARP application entity.

This section covers these topics:

l           GARP messages and timers

l           Operating mechanism of GARP

l           GARP message format

I. GARP messages and timers

1)         GARP messages

A GARP participant exchanges information with other GARP participants mainly by sending the following three types of messages:

l           Join to register some attribute with other participants.

l           Leave to deregister some attribute with other participants.

l           LeaveAll to deregister all attributes. A LeaveAll message is sent upon expiration of the LeaveAll timer, which starts upon the startup of a GARP application entity. Upon receiving a LeaveAll message, all other GARP entities on the LAN re-register the attributes of the message sending GARP entity.

GARP participants thus use the three messages to complete attribute reregistration and deregistration.

Through message exchange, all attribute information to be registered propagates to all GARP participants throughout the LAN.

2)         GARP timers

GARP uses the following four timers to set the interval sending GARP messages:

l           Hold timer — When a GARP application entity receives the first registration request, it starts the Hold timer and collects succeeding requests. When the timer expires, the entity sends all these requests in one Join message, thus saving bandwidth.

l           Join timer –– A GARP application entity sends each Join message twice for reliability sake and uses the Join timer to set the interval between the two sending operations.

l           Leave timer –– Starts upon receipt of a Leave message. If no Join message has been received from the requesting entity before this timer expires, the GARP application entity removes the attribute information as requested.

l           LeaveAll timer — Starts when a GARP application entity starts. When this timer expires, the entity sends a LeaveAll message so that other entities can re-register all its attribute information, and, at the same time, it restarts the LeaveAll timer.

 

 

II. Operating mechanism of GARP

The GARP mechanism allows the configuration of a GARP participant to propagate throughout a LAN quickly.

In GARP, a GARP participant registers or deregisters its attributes with other participants by making or withdrawing declarations of attributes and at the same time, based on received declarations or withdrawals, registers or deregisters the attributes of other participants.

GARP application entities send protocol data units (PDU) with a particular multicast MAC address as destination. Based on this address, a device can identify to which GVRP application, GVRP for example, a GARP PDU should be delivered.

III. GARP message format

The following figure illustrates the format of GARP messages, which are carried in GARP PDUs.

Figure 1-1 GARP message format

The following table describes the GARP message fields.

Table 1-1 Description on the GARP message fields

Field	Description	Value
Protocol ID	Protocol identifier for GARP	1
Message	Each message contains an attribute type and an attribute list	––
Attribute Type	Defined by the concerned GARP application	0x01 for GVRP, indicating the VLAN ID attribute
Attribute List	Contains one or multiple attributes	––
Attribute	Consists of an Attribute Length, an Attribute Event, and an Attribute Value	––
Attribute Length	Number of octets occupied by an attribute, inclusive of the attribute length field	2 to 255 in bytes
Attribute Event	Event described by the attribute	0: LeaveAll Event 1: JoinEmpty Event 2: JoinIn Event 3: LeaveEmpty Event 4: LeaveIn Event 5: Empty Event
Attribute Value	Attribute value	VLAN ID for GVRP If the Attribute Event is LeaveAll, Attribute Value is omitted.
End Mark	Indicates the end of PDU	Expressed in 0x00

 

1.1.2  GVRP

GVRP enables a device to propagate local VLAN registration information to other participant devices and dynamically update the VLAN registration information from other devices to its local database about active VLAN members and through which port they can be reached. It thus ensures that all GVRP participants on a 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 provides the following three registration modes on a port:

l           Normal — Enables the port to dynamically register and deregister VLANs, and to propagate both dynamic and static VLAN information.

l           Fixed –– Disables the port to dynamically register and deregister VLANs or propagate information about dynamic VLANs, but allows the port to propagate information about static VLANs. A trunk port in fixed registration mode thus allows only manually configured VLANs to pass through even though it is configured to carry all VLANs.

l           Forbidden –– Disables the port to dynamically register and deregister VLANs and to propagate VLAN information except information about VLAN 1. A trunk port in forbidden registration mode thus allows only VLAN 1 to pass through even though it is configured to carry all VLANs.

1.1.3  Protocols and Standards

IEEE 802.1Q specifies GVRP.

1.2  Configuring GVRP

GVRP configuration includes configuring GVRP functions and configuring GARP timers.

1.2.1  Configuring GVRP Functions

Follow these steps to configure GVRP functions on a trunk port:

To do…		Use the command…	Remarks
Enter system view		system-view	––
Enable global GVRP		gvrp	Required Disabled by default
Enter Ethernet interface view or port-group view	Enter Ethernet interface view	interface interface-type interface-number	Required Perform either of the commands. Depending on the view you accessed, the subsequent configuration takes effect on a port or all ports in a port-group.
	Enter port-group view	port-group { manual port-group-name | aggregation agg-id }
Enable GVRP on the port		gvrp	Required Disabled by default
Configure the GVRP registration mode on the port		gvrp registration { fixed | forbidden | normal }	Optional The default is normal.

 

 

1.2.2  Configuring GARP Timers

Follow these steps to configure GARP timers:

To do…		Use the command…	Remarks
Enter system view		system-view	––
Configure the GARP LeaveAll timer		garp timer leaveall timer-value	Optional The default is 1000 centiseconds.
Enter Ethernet interface view or port-group view	Enter Ethernet interface view	interface interface-type interface-number	Required Perform either of the commands. Depending on the view you accessed, the subsequent configuration takes effect on a port or all ports in a port-group.
	Enter port-group view	port-group { manual port-group-name | aggregation agg-id }
Configure the Hold timer, Join timer, or Leave timer		garp timer { hold | join | leave } timer-value	Optional The default is 10 centiseconds for the Hold timer, 20 centiseconds for the Join timer, and 60 centiseconds for the Leave timer.

 

When configuring GARP timers, note that their values are dependent on each other and must be a multiple of five centiseconds. If the value range for a timer is not desired, you may change it by tuning the value of another related timer as shown in the following table:

Table 1-2 Dependencies of GARP timers

Timer	Lower limit	Upper limit
Hold	10 centiseconds	Not greater than half of the Join timer setting
Join	Not less than two times the Hold timer setting	Less than half of the Leave timer setting
Leave	Greater than two times the Join timer setting	Less than the LeaveAll timer setting
LeaveAll	Greater than the Leave timer setting	32765 centiseconds

 

1.3  Displaying and Maintaining GVRP

To do…	Use the command…	Remarks
Display statistics about GARP	display garp statistics [ interface interface-list ]	Available in any view
Display GARP timers for specified or all ports	display garp timer [ interface interface-list ]	Available in any view
Display statistics about GVRP	display gvrp statistics [ interface interface-list ]	Available in any view
Display the global GVRP state	display gvrp status	Available in any view
Clear the GARP statistics	reset garp statistics [ interface interface-list ]	Available in user view

 

1.4  GVRP Configuration Example

1.4.1  GVRP Configuration Example I

I. Network requirements

Configure GVRP for dynamic VLAN information registration and update between the switches. The trunk ports are in the default “normal” registration mode.

II. Network diagram

Figure 1-2 Network diagram for GVRP configuration

III. Configuration procedure

1)         Configure Switch A

# Enable GVRP globally.

<SysnameA> system-view

[SysnameA] gvrp

# Configure port Ethernet 1/1/1 as a trunk port, allowing all VLANs to pass.

[SysnameA] interface ethernet 1/1/1

[SysnameA-Ethernet1/1/1] port link-type trunk

[SysnameA-Ethernet1/1/1] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/1, the trunk port.

[SysnameA-Ethernet1/1/1] gvrp

[SysnameA-Ethernet1/1/1] quit

# Create VLAN 2 (a static VLAN).

[SysnameA] vlan 2

[SysnameA-vlan2] return

2)         Configure Switch B

# Enable GVRP globally.

<SysnameB> system-view

[SysnameB] gvrp

# Configure port Ethernet 1/1/2 as a trunk port, allowing all VLANs to pass.

[SysnameB] interface ethernet 1/1/2

[SysnameB-Ethernet1/1/2] port link-type trunk

[SysnameB-Ethernet1/1/2] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/2, the trunk port.

[SysnameB-Ethernet1/1/2] gvrp

[SysnameB-Ethernet1/1/2] quit

# Create VLAN 3 (a static VLAN).

[SysnameB] vlan 3

[SysnameB-vlan3] return

3)         Verify the configuration

# Display dynamic VLAN information on Switch A.

<SysnameA> display vlan dynamic

Total 1 dynamic VLAN exist(s).

 The following dynamic VLANs exist:

  3

# Display dynamic VLAN information on Switch B.

<SysnameB> display vlan dynamic

Total 1 dynamic VLAN exist(s).

 The following dynamic VLANs exist:

  2

1.4.2  GVRP Configuration Example II

I. Network requirements

Configure GVRP for dynamic VLAN information registration and update between the switches. Set the “fixed” GVRP registration mode on the trunk port of Switch A and keep the default “normal” GVRP registration mode on the trunk port of Switch B.

II. Network diagram

Figure 1-3 Network diagram for GVRP configuration

III. Configuration procedure

1)         Configure Switch A

# Enable GVRP globally.

<SysnameA> system-view

[SysnameA] gvrp

# Configure port Ethernet 1/1/1 as a trunk port, allowing all VLANs to pass.

[SysnameA] interface ethernet 1/1/1

[SysnameA-Ethernet1/1/1] port link-type trunk

[SysnameA-Ethernet1/1/1] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/1.

[SysnameA-Ethernet1/1/1] gvrp

# Set the GVRP registration mode to fixed on the port.

[SysnameA-Ethernet1/1/1] gvrp registration fixed

[SysnameA-Ethernet1/1/1] quit

# Create VLAN 2 (a static VLAN).

[SysnameA] vlan 2

[SysnameA-vlan2] return

2)         Configure Switch B

# Enable GVRP globally.

<SysnameB> system-view

[SysnameB] gvrp

# Configure port Ethernet 1/1/2 as a trunk port, allowing all VLANs to pass.

[SysnameB] interface ethernet 1/1/2

[SysnameB-Ethernet1/1/2] port link-type trunk

[SysnameB-Ethernet1/1/2] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/2.

[SysnameB-Ethernet1/1/2] gvrp

[SysnameB-Ethernet1/1/2] quit

# Create VLAN 3 (a static VLAN).

[SysnameB] vlan 3

[SysnameB-vlan3] return

3)         Verify the configuration

# Display dynamic VLAN information on Switch A.

<SysnameA> display vlan dynamic

No dynamic VLAN exists!

# Display dynamic VLAN information on Switch B.

<SysnameB> display vlan dynamic

Total 1 dynamic VLAN exist(s).

 The following dynamic VLANs exist:

  2

1.4.3  GVRP Configuration Example III

I. Network requirements

Configure GVRP for dynamic VLAN information registration and update between the switches. Set the “forbidden” GVRP registration mode on the trunk port of Switch A and keep the default “normal” mode on the trunk port of Switch B.

II. Network diagram

Figure 1-4 Network diagram for GVRP configuration

III. Configuration procedure

1)         Configure Switch A

# Enable GVRP globally.

<SysnameA> system-view

[SysnameA] gvrp

# Configure port Ethernet 1/1/1 as a trunk port, allowing all VLANs to pass.

[SysnameA] interface ethernet 1/1/1

[SysnameA-Ethernet1/1/1] port link-type trunk

[SysnameA-Ethernet1/1/1] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/1.

[SysnameA-Ethernet1/1/1] gvrp

# Set the GVRP registration mode to forbidden on the port.

[SysnameA-Ethernet1/1/1] gvrp registration forbidden

[SysnameA-Ethernet1/1/1] quit

# Create VLAN 2 (a static VLAN).

[SysnameA] vlan 2

[SysnameA-vlan2] return

2)         Configure Switch B

# Enable GVRP globally.

<SysnameB> system-view

[SysnameB] gvrp

# Configure port Ethernet 1/1/2 as a trunk port, allowing all VLANs to pass.

[SysnameB] interface ethernet 1/1/2

[SysnameB-Ethernet1/1/2] port link-type trunk

[SysnameB-Ethernet1/1/2] port trunk permit vlan all

# Enable GVRP on Ethernet 1/1/2.

[SysnameB-Ethernet1/1/2] gvrp

[SysnameB-Ethernet1/1/2] quit

# Create VLAN 3 (a static VLAN).

[SysnameB] vlan 3

[SysnameB-vlan3] return

3)         Verify the configuration

# Display dynamic VLAN information on Switch A.

<SysnameA> display vlan dynamic

No dynamic VLAN exists!

# Display dynamic VLAN information on Switch B.

<SysnameB> display vlan dynamic

No dynamic VLAN exists!