How to disable STP on a per port basis in Cisco Catalyst 2900XL - 2940 - 2950 - 2960 - 2970 - 3500XL - 3550 - 3560 - 3750 - 4000 - 4500 - 5000 - 5500 - 6000 - 6500 switches.
By default, spanning tree runs on every port.
The spanning tree feature cannot be turned off in switches on a per port basis.
Although it is not recommended, you can turn off Spanning Tree Protocol (STP) on a per-VLAN basis, or globally on the switch.
Use the no spanning-tree vlan vlan-id command in order to disable STP on a per virtual LAN (VLAN) basis.
Also ensure that all switches and bridges in the VLAN have spanning tree disabled.
You can't disable spanning tree on some switches and bridges in a VLAN and leave it enabled on other switches and bridges in the VLAN.
If you do this, you can have unexpected results because switches and bridges with spanning tree enabled have incomplete information in regards to the physical topology of the network.
Note:
Extreme care needs to be taken whenever you disable spanning tree because this creates Layer 2 loops within the network.
Do not disable spanning tree in a VLAN, and make sure that there are no physical loops present in the VLAN.
For further information refer to:
Understanding and Configuring Spanning Tree Protocol (STP) on Catalyst Switches
| Brad Reese Profile |
About Brad Reese on Cisco
Brad Reese is research manager at BradReese.Com, advancing the careers of 1 million certified individuals in the growing Cisco Career Certification Program.
Contact him.
Brad's blogroll
Brad Reese on Cisco archive.
Cisco Subnet
|
|
spanning-tree bpdufilter enable
The spanning-tree bpdufilter enable command on an interface is approximately equivalent to disabling the spanning tree for this interface.
http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.1E/native/command/reference/S1.html#wp1179280
BPDU filtering allows you to prevent a port from sending and receiving BPDUs. The configuration is applicable to the whole interface, whether it is trunking or not. This command has three states:
•spanning-tree bpdufilter enable—This state unconditionally enables the BPDU filter feature on the interface.
•spanning-tree bpdufilter disable—This state unconditionally disables the BPDU filter feature on the interface.
•no spanning-tree bpdufilter—This state enables the BPDU filter feature on the interface if the interface is in operational PortFast state and if the spanning-tree portfast bpdufilter default command is configured.