Cisco WS-C2980G-A Software Guide - Page 274

Sending GVRP VLAN Declarations from Blocking Ports, Setting the GARP Timers

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Configuring GVRP on the Switch Chapter 13 Configuring GVRP Sending GVRP VLAN Declarations from Blocking Ports To prevent undesirable Spanning Tree Protocol (STP) topology reconfiguration on a port that is connected to a device that does not support per-VLAN STP, configure the GVRP active applicant state on the port. Ports in the GVRP active applicant state send GVRP VLAN declarations when they are in the STP blocking state, which prevents the STP bridge protocol data units (BPDUs) from being pruned from the other port. Note Configuring fixed registration on the other device's port would also prevent undesirable STP topology reconfiguration. To configure an 802.1Q trunk port to send VLAN declarations when in the blocking state, perform this task in privileged mode: Task Configure an 802.1Q trunk port to send VLAN declarations when in the blocking state. Command set gvrp applicant state {normal | active} mod_num/port_num This example shows how to configure a group of 802.1Q trunk ports to send VLAN declarations when in the blocking state: Console> (enable) set gvrp applicant active 4/2-3,4/9-10,4/12-24 Applicant was set to active on port(s) 4/2-3,4/9-10,4/12-24. Console> (enable) Use the normal keyword to return to the default state (active mode disabled). Setting the GARP Timers Note The commands set gvrp timer and show gvrp timer are aliases for set garp timer and show garp timer. The aliases may be used if desired. Note Modifying the GARP timer values affects the behavior of all GARP applications running on the switch, not just GVRP. (For example, GMRP uses the same timers.) You can modify the default GARP timer values on the switch. When you set the timer values, the value for leave must be greater than three times the join value (leave >= join * 3). The value for leaveall must be greater than the value for leave (leaveall > leave). If you attempt to set a timer value that does not adhere to these rules, an error message is displayed. For example, if you set the leave timer to 600 ms and you attempt to configure the join timer to 350 ms, an error message is displayed. Set the leave timer to at least 1050 ms, and then set the join timer to 350 ms. 13-6 Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide-Release 8.1 78-15486-01

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13-6
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide
Release 8.1
78-15486-01
Chapter 13
Configuring GVRP
Configuring GVRP on the Switch
Sending GVRP VLAN Declarations from Blocking Ports
To prevent undesirable Spanning Tree Protocol (STP) topology reconfiguration on a port that is
connected to a device that does not support per-VLAN STP, configure the GVRP active applicant state
on the port. Ports in the GVRP active applicant state send GVRP VLAN declarations when they are in
the STP blocking state, which prevents the STP bridge protocol data units (BPDUs) from being pruned
from the other port.
Note
Configuring fixed registration on the other device’s port would also prevent undesirable STP topology
reconfiguration.
To configure an 802.1Q trunk port to send VLAN declarations when in the blocking state, perform this
task in privileged mode:
This example shows how to configure a group of 802.1Q trunk ports to send VLAN declarations when
in the blocking state:
Console> (enable)
set gvrp applicant active 4/2-3,4/9-10,4/12-24
Applicant was set to active on port(s) 4/2-3,4/9-10,4/12-24.
Console> (enable)
Use the
normal
keyword to return to the default state (active mode disabled).
Setting the GARP Timers
Note
The commands
set gvrp timer
and
show gvrp timer
are aliases for
set garp timer
and
show garp timer
.
The aliases may be used if desired.
Note
Modifying the GARP timer values affects the behavior of
all
GARP applications running on the switch,
not just GVRP. (For example, GMRP uses the same timers.)
You can modify the default GARP timer values on the switch.
When you set the timer values, the value for
leave
must be greater than three times the
join
value
(
leave >= join *
3). The value for
leaveall
must be greater than the value for
leave
(
leaveall
>
leave
).
If you attempt to set a timer value that does not adhere to these rules, an error message is displayed. For
example, if you set the
leave
timer to 600 ms and you attempt to configure the
join
timer to 350 ms, an
error message is displayed. Set the
leave
timer to at least 1050 ms, and then set the
join
timer to 350 ms.
Task
Command
Configure an 802.1Q trunk port to send VLAN
declarations when in the blocking state.
set gvrp applicant state
{
normal
|
active
}
mod_num/port_num