H3C Technologies H3C S12500 Series Switches - Manual (Page 186)

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Set the LeaveAll timer greater than any Leave timer and not smaller than its default value (1000
centiseconds). Each time a LeaveAll timer expires, a network-wide re-join occurs.
On a GARP-enabled network, a device can send LeaveAll messages at the interval set by its
LeaveAll timer or the LeaveAll timer of another device on the network, whichever is smaller. This is
because each time a device on the network receives a LeaveAll message it resets its LeaveAll timer.
The settings of GARP timers apply to all GARP applications, such as GVRP, on a LAN.
On a GARP-enabled network, each port of a device maintains its own Hold, Join, and Leave timers, but
only one LeaveAll timer is maintained on each device globally.
The value ranges for the Hold, Join, Leave, and LeaveAll timers are dependent on one another. For more
information, see Table 20 .
GARP PDU format
Figure 61 GARP PDU format
As shown in Figure 61 , GARP PDUs use the IEEE 802.3 Ethernet frame format.
Table 19 The GARP PDU fields
Field Description Value
Protocol ID Protocol identifier for GARP. 0x0001
Message
One or multiple messages, each
containing an attribute type and an
attribute list.
N/A
End mark Indicates the end of a GARP PDU. 0x00
Attribute type Defined by the GARP application.
0x01 for GVRP, indicating the
VLAN ID attribute
Attribute list Contains one or multiple attributes. N/A
Attribute
Consists of an Attribute Length, an
Attribute Event, and an Attribute
Value.
N/A