7-37
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
OL-8978-04
Chapter 7 Configuring Spanning Tree
Configuring MISTP-PVST+ or MISTP on the Switch
14 00-50-3e-78-70-00 -
15 00-50-3e-78-70-00 -
16 00-50-3e-78-70-00 -
Configuring an MISTP Instance
These sections describe how to configure MISTP instances:
•
Configuring the MISTP Bridge ID Priority, page 7-37
•
Configuring the MISTP Port Cost, page 7-38
•
Configuring the MISTP Port Priority, page 7-39
•
Configuring the MISTP Port Instance Cost, page 7-40
•
Configuring the MISTP Port Instance Priority, page 7-40
Configuring the MISTP Bridge ID Priority
You can set the bridge ID priority for an MISTP instance when the switch is in MISTP or MISTP-PVST+
mode.
The bridge priority value is combined with the system ID extension (the ID of the MISTP instance) to
create the bridge ID priority. You can set 16 possible bridge priority values: 0, 4096, 8192, 12288, 16384,
20480, 24576, 28672, 32768, 36864, 40960, 45056, 49152, 53248, 57344, and 61440.
To configure the bridge ID priority for an MISTP instance, perform this task in privileged mode:
This example shows how to configure the bridge ID priority for an MISTP instance:
Console> (enable)
set spantree priority 32768 mistp-instance 1
Spantree 1 bridge ID priority set to 32769
(bridge priority: 32768 + sys ID extension: 1)
Console> (enable)
show spantree mistp-instance 1
Instance 1
Spanning tree mode MISTP
Spanning tree type ieee
Spanning tree instance enabled
Designated Root 00-05-31-40-64-00
Designated Root Priority 32769 (root priority:32768, sys ID ext:1)
Designated Root Cost 20000
Designated Root Port 1/1
VLANs mapped: 1,74
Root Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec
Bridge ID MAC ADDR 00-d0-02-27-9c-00
Bridge ID Priority 32769 (bridge priority:32768, sys ID ext:1)
VLANs mapped: 1,74
Bridge Max Age 20 sec Hello Time 2 sec Forward Delay 15 sec
Task
Command
Step 1
Configure the bridge ID priority for an
MISTP instance.
set spantree priority
bridge_ID_priority
[
mistp-instance
instance
]
Step 2
Verify the bridge ID priority.
show spantree mistp-instance
instance
[
mod/port
]
active