garp timer

Function

The garp timer command sets GARP timers.

The undo garp timer command restores the default values of GARP timers.

By default, the value of the Hold timer is 10 centiseconds, the value of the Join timer is 20 centiseconds, and the value of the Leave timer is 60 centiseconds.

Format

garp timer { hold | join | leave } timer-value

undo garp timer { hold | join | leave } [ timer-value ]

Parameters

Parameter	Description	Value
hold timer-value	Sets the value of the GARP Hold timer.	Lower limit: 10 centiseconds Upper limit: less than or equal to half the value of the Join timer, changing with the value of the Join timer The value can be exactly divided by 5, in centiseconds.
join timer-value	Sets the value of the GARP Join timer.	Lower limit: greater than or equal to two times the value of the Hold timer, changing with the value of the Hold timer Upper limit: smaller than half the value of the Leave timer, changing with the value of the Leave timer The value can be exactly divided by 5, in centiseconds.
leave timer-value	Sets the value of the GARP Leave timer.	Lower limit: greater than two times the value of the Join timer, changing with the value of the Join timer Upper limit: smaller than the value of the LeaveAll timer, changing with the value of the LeaveAll timer The value can be exactly divided by 5, in centiseconds.

Views

Ethernet interface view, GE interface view, XGE interface view, MultiGE interface view, 100GE interface view, 40GE interface view, 100GE interface view, port group view, Eth-Trunk interface view, 25GE interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

This command can set the following GARP timers:

Join timer: controls sending of Join messages including JoinIn messages and JoinEmpty messages.
Hold timer: controls sending of Join messages (JoinIn messages and JoinEmpty messages) and Leave messages (LeaveIn messages and LeaveEmpty messages).
Leave timer: controls attribute deregistration.

You can set the GARP timers to control sending of GARP protocol packets.

Prerequisite

The physical port has been added to the port group before running the garp timer command in the port group view.

Before setting garp timers on an interface, you must enable GVRP globally and on the interface.

Precautions

When using the garp timer command to set the GARP timers, pay attention to the following points:

The garp timer can be used only on trunk interfaces.
The undo garp timer command restores the default values of GARP timers. If the default value of a timer is out of the valid range, the undo garp timer command does not take effect.
The value range of each timer changes with the values of the other timers. If a value you set for a timer is not in the allowed range, you can change the value of the timer that determines the value range of this timer.
To restore the default values of all the GARP timers, restore the Hold timer to the default value, and then restore the Join timer, Leave timer, and LeaveAll timer to the default values in sequence.

When many dynamic VLANs need to be registered or the network radius is large, using default values of timers may cause VLAN flapping and high CPU usage. In this case, increase values of the timers. The following values are recommended depending on the number of VLANs.

**Table 1** Relationship between GARP timer values and number of dynamic VLANs that need to be registered
Timer	Number of Dynamic VLANs to Be Registered (N)
Timer	N <= 500	500 < N <= 1000	1000 < N <= 1500	N > 1500
GARP Hold timer	100 centiseconds (1 second)	200 centiseconds (2 seconds)	800 centiseconds (8 seconds)	1000 centiseconds (10 seconds)
GARP Join timer	600 centiseconds (6 seconds)	1200 centiseconds (12 seconds)	4000 centiseconds (40 seconds)	6000 centiseconds (1 minute)
GARP Leave timer	3000 centiseconds (30 seconds)	6000 centiseconds (1 minute)	20000 centiseconds (3 minutes and 20 seconds)	30000 centiseconds (5 minutes)
GARP LeaveAll timer	12000 centiseconds (2 minutes)	24000 centiseconds (4 minutes)	30000 centiseconds (5 minutes)	32765 centiseconds (5 minutes and 27.65 seconds)

Example

# Set the LeaveALL timer of GigabitEthernet0/0/1 to 2000 centiseconds.

<HUAWEI> system-view
[HUAWEI] garp timer leaveall 2000

# Set the Leave timer of GigabitEthernet 0/0/1 to 800 centiseconds.

<HUAWEI> system-view
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] port link-type trunk
[HUAWEI-GigabitEthernet0/0/1] garp timer leave 800

# Set the Join timer of GigabitEthernet 0/0/1 to 300 centiseconds.

<HUAWEI> system-view
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] port link-type trunk
[HUAWEI-GigabitEthernet0/0/1] garp timer join 300

# Set the Hold timer of GigabitEthernet 0/0/1 to 100 centiseconds.

<HUAWEI> system-view
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] port link-type trunk
[HUAWEI-GigabitEthernet0/0/1] garp timer hold 100