Table of Contents

Chapter 1 GVRP Configuration. 1-1

1.1 Introduction to GARP and GVRP. 1-1

1.1.1 Introduction to GARP. 1-1

1.1.2 GVRP Mechanism.. 1-2

1.1.3 GVRP Packet Format 1-3

1.1.4 Protocol Specifications. 1-4

1.2 GVRP Configuration. 1-4

1.2.1 Configuration Prerequisite. 1-4

1.2.2 Configuration Procedure. 1-4

1.3 Displaying and Maintaining GVRP. 1-6

1.4 GVRP Configuration Examples. 1-7

1.4.1 Network requirements. 1-7

1.4.2 Network diagram.. 1-7

1.4.3 Configuration procedure. 1-7

 

Chapter 1  GVRP Configuration

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

l           Introduction to GARP and GVRP

l           GVRP Configuration

l           Displaying and Maintaining GVRP

l           GVRP Configuration Examples

1.1  Introduction to GARP and GVRP

1.1.1  Introduction to GARP

Generic Attribute Registration Protocol (GARP) offers a mechanism that is used by the members in the same switching network to distribute, propagate and register such information as VLAN and multicast addresses.

GARP dose not exist in a switch as an entity. A GARP participant is called GARP application. The main GARP applications at present are GVRP and GMRP. GVRP is described in the section GVRP Mechanism and GMRP will be described in Multicast Configuration. When a GARP participant is on a port of the switch, each port corresponds to a GARP participant.

Through GARP mechanism, the configuration information on one GARP member will be advertised rapidly in the whole switching network. GARP member can be a terminal workstation or bridge. A GARP member can notify other members to register or remove its attribute information by sending declarations or withdrawal declarations. It can also register or remove the attribute information of other GARP members according to the received declarations/withdrawal declarations.

GARP members exchange information through sending messages. There are mainly three types of GARP messages including Join, Leave, and LeaveAll.

l           When a GARP participant wants to register its attribute information on other switches, it will send Join message outward.

l           When it wants to remove some attribute values from other switches, it will send Leave message.

l           LeaveAll timer will be started at the same time when each GARP participant is enabled and LeaveAll message will be sent upon timeout.

The Join message and the Leave message are used together to complete the deregistration and re-registration of information. Through exchanging messages, all the attribute information to be registered can be propagated to all the switches in the same switching network.

The destination MAC addresses of the packets of the GARP participants are specific multicast MAC addresses. A GARP-supporting switch will classify the packets received from the GARP participants and process them with corresponding GARP applications (GVRP or GMRP).

GARP and GMRP are described in details in the IEEE 802.1p standard (which has been added to the IEEE802.1D standard). H3C Series Ethernet Switches fully support the GARP compliant with the IEEE standards.

 

 

1.1.2  GVRP Mechanism

I. GARP Timers

GARP timers include Hold timer, Join timer, Leave timer and LeaveAll timer.

l           Hold: When a GARP participant receives a piece of registration information, it does not send out a Join message immediately. Instead, to save the bandwidth resources, it starts the Hold timer, puts all registration information it receives before the timer times out into one Join message and sends out the message after the timer times out.

l           Join: To transmit the Join messages reliably to other entities, a GARP participant sends each Join message two times. The Join timer is used to define the interval between the two sending operations of each Join message.

l           Leave: When a GARP participant expects to unregister a piece of attribute information, it sends out a Leave message. Any GARP participant receiving this message starts its Leave timer, and unregisters the attribute information if it does not receives a Join message again before the timer times out.

l           LeaveAll: Once a GARP participant starts up, it starts the LeaveAll timer, and sends out a LeaveALL message after the timer times out, so that other GARP participants can re-register all the attribute information on this participant. After that, the participant restarts the LeaveAll timer to begin a new cycle.

II. GVRP port registration mode

GVRP has the following three port registration modes: Normal, Fixed, and Forbidden.

l           Normal: In this mode, a port can dynamically register/deregister a VLAN and propagate the dynamic/static VLAN information.

l           Fixed: In this mode, a port cannot register/deregister a VLAN dynamically. It only propagates static VLAN information. That is, a trunk port only permits the packets of manually configured VLANs in this mode even if you configure the port to permit the packets of all the VLANs.

l           Forbidden: In this mode, a port cannot register/deregister VLANs. It only propagates VLAN 1 information. That is, a trunk port only permits the packets of the default VLAN (namely VLAN 1) in this mode even if you configure the port to permit the packets of all the VLANs.

III. GARP operation procedure

Through the mechanism of GARP, the configuration information on a GARP member will be propagated to the entire switched network. A GARP can be a terminal workstation or a bridge; it instructs other GARP member to register/unregister its attribute information by declaration/recant, and register/unregister other GARP member's attribute information according to other member's declaration/recant.

The protocol packets of GARP entity use specific multicast MAC addresses as their destination MAC addresses. When receiving these packets, the switch distinguishes them by their destination MAC addresses and delivers them to different GARP application (for example, GVRP) for further processing.

1.1.3  GVRP Packet Format

The GVRP packets are in the following format:

Figure 1-1 Format of GVRP packets

The following table describes the fields of a GVRP packet.

Table 1-1 Description of GVRP packet fields

Field	Description	Value
Protocol ID	Protocol ID	1
Message	Each message consists of two parts: Attribute Type and Attribute List.	—
Attribute Type	Defined by the specific GARP application	The attribute type of GVRP is 0x01.
Attribute List	It contains multiple attributes.	—
Attribute	Each general attribute consists of three parts: Attribute Length, Attribute Event and Attribute Value. Each LeaveAll attribute consists of two parts: Attribute Length and LeaveAll Event.	—
Attribute Length	The length of the attribute	2 to 255
Attribute Event	The event described by the attribute	0: LeaveAll Event 1: JoinEmpty 2: JoinIn 3: LeaveEmpty 4: LeaveIn 5: Empty
Attribute Value	The value of the attribute	The attribute value of GVRP is the VID.
End Mark	End mark of the GVRP PDU.	—

 

1.1.4  Protocol Specifications

GVRP is defined in IEEE 802.1Q standard.

1.2  GVRP Configuration

The GVRP configuration tasks include configuring the GARP timers, enabling GVRP, and configuring the GVRP port registration mode.

1.2.1  Configuration Prerequisite

The port on which GVRP will be enabled must be set to a trunk port.

1.2.2  Configuration Procedure

Follow these steps to configure GVRP:

To do…	Use the command…	Remarks
Enter system view	system-view	—
Configure the LeaveAll timer	garp timer leaveall timer-value	Optional By default, the LeaveAll timer is set to 1,000 centiseconds.
Enter Ethernet port view	interface interface-type interface-number	—
Configure the Hold, Join, and Leave timers	garp timer { hold | join | leave } timer-value	Optional By default, the Hold, Join, and Leave timers are set to 10, 20, and 60 centiseconds respectively.
Exit and return to system view	quit	—
Enable GVRP globally	gvrp	Required By default, GVRP is disabled globally.
Enter Ethernet port view	interface interface-type interface-number	—
Enable GVRP on the port	gvrp	Required By default, GVRP is disabled on the port. After you enable GVRP on a trunk port, you cannot change the port to a different type.
Configure GVRP port registration mode	gvrp registration { fixed | forbidden | normal }	Optional You can choose one of the three modes. By default, GVRP port registration mode is normal.

 

The timeout ranges of the timers vary depending on the timeout values you set for other timers. If you want to set the timeout time of a timer to a value out of the current range, you can set the timeout time of the associated timer to another value to change the timeout range of this timer.

The following table describes the relations between the timers:

Table 1-2 Relations between the timers

Timer	Lower threshold	Upper threshold
Hold	10 centiseconds	This upper threshold is less than or equal to one-half of the timeout time of the Join timer. You can change the threshold by changing the timeout time of the Join timer.
Join	This lower threshold is greater than or equal to twice the timeout time of the Hold timer. You can change the threshold by changing the timeout time of the Hold timer.	This upper threshold is less than one-half of the timeout time of the Leave timer. You can change the threshold by changing the timeout time of the Leave timer.
Leave	This lower threshold is greater than twice the timeout time of the Join timer. You can change the threshold by changing the timeout time of the Join timer.	This upper threshold is less than the timeout time of the LeaveAll timer. You can change the threshold by changing the timeout time of the LeaveAll timer.
LeaveAll	This lower threshold is greater than the timeout time of the Leave timer. You can change threshold by changing the timeout time of the Leave timer.	32,765 centiseconds

 

 

1.3  Displaying and Maintaining GVRP

To do…	Use the command…	Remarks
Display GARP statistics	display garp statistics [ interface interface-list ]	Available in any view.
Display the settings of the GARP timers	display garp timer [ interface interface-list ]
Display GVRP statistics	display gvrp statistics [ interface interface-list ]
Display the global GVRP status	display gvrp status
Clear GARP statistics	reset garp statistics [ interface interface-list ]	Available in user view.

 

1.4  GVRP Configuration Examples

1.4.1  Network requirements

You need to enable GVRP on the switches to enable dynamic VLAN information registration and update between the switches.

1.4.2  Network diagram

Figure 1-2 Network diagram for GVRP configuration

1.4.3  Configuration procedure

l           Configure switch A.

# Enable GVRP globally.

<H3C> system-view

[H3C] gvrp

GVRP is enabled globally.

# Configure port Ethernet 1/0/1 to be a trunk port and to permit the packets of all the VLANs.

[H3C] interface Ethernet1/0/1

[H3C-Ethernet1/0/1] port link-type trunk

[H3C-Ethernet1/0/1] port trunk permit vlan all

# Enable GVRP on the trunk port.

[H3C-Ethernet1/0/1] gvrp

GVRP is enabled on port Ethernet1/0/1.

l           Configure switch B.

# Enable GVRP globally.

<H3C> system-view

[H3C] gvrp

GVRP is enabled globally.

# Configure port Ethernet 1/0/2 to be a trunk port and to permit the packets of all the VLANs.

[H3C] interface Ethernet1/0/2

[H3C-Ethernet1/0/2] port link-type trunk

[H3C-Ethernet1/0/2] port trunk permit vlan all

# Enable GVRP on the trunk port.

[H3C-Ethernet1/0/2] gvrp

GVRP is enabled on port Ethernet1/0/2.