Configuring Spanning Tree Protocol (STP)
To remove a Fast Uplink Span group or to remove individual ports from a group, use “no” in front of the appropriate fast uplink-spancommand. For example, to remove ports 4/3 and 4/4 from the Fast Uplink Span group configured above, enter the following commands:
HP9300(config)# no fast uplink-span ethernet 4/3 to 4/4
HP9300(config)# write memory
If you delete a port that is the primary port of a trunk group, all ports in the trunk group are removed from the Fast Uplink Span group.
USING THE WEB MANAGEMENT INTERFACE
You cannot configure the Fast Uplink Span feature using the Web management interface.
Single Spanning Tree
In software releases earlier than 05.2.16, each port-based VLAN runs a separate spanning tree, which you can enable or disable on an individual VLAN basis. This is still the default behavior in software release 06.6.X and later. However, this software release enhances HP’s STP support by enabling you to configure a single instance of the Spanning Tree Protocol (STP) to run on all the port-based VLANs on a device.
The single STP feature is especially useful for connecting an HP device to other devices that run a single spanning tree in accordance with the 802.1q specification.
Single-instance STP uses the same parameters, with the same value ranges and defaults, as the default STP on HP devices (multiple-instance STP).
STP Defaults
STP is enabled by default on switches and disabled by default on routing switches. On switches and routing switches, each port-based VLAN runs a separate instance of STP by default. Thus, on devices that have multiple port-based VLANs, each VLAN has its own spanning tree domain. In addition, the STP state of each port-based VLAN is independent of the STP states of other VLANs. You can have STP enabled on port-based VLAN 10, but disabled on port-based VLANs 20 and 30, and so on.
When you configure a port-based VLAN, that VLAN inherits the STP state of the default port-based VLAN. Thus, if STP is enabled on the default VLAN, STP is also enabled on the new port-based VLAN. You can change the STP state of the VLAN afterwards. Changes to the STP state of the default VLAN do not affect existing VLANs. A change to the STP state affects only the VLANs you create after the change.
Single STP and Existing Port-Based VLANs
When you enable single STP, all the ports on the device become members of a single spanning tree domain. Thus, the ports share a single BPDU broadcast domain. The HP device places all the ports in a non-configurable VLAN, 4094, to implement the single STP domain. However, this VLAN does not affect port membership in the port-based VLANs you have configured. Other broadcast traffic is still contained within the individual port-based VLANs. Therefore, you can use single STP while still using your existing VLAN configurations without changing your network. In addition, single STP does not affect 802.1q tagging. Tagged and untagged ports alike can be members of the single spanning tree domain.
NOTE: When single STP is enabled, the BPDUs on tagged ports go out untagged.
NOTE: If STP is disabled on a VLAN, you must enable STP on the VLAN before enabling single STP.
Spanning Tree Parameters
The STP parameters behave the same and have the same defaults and possible values whether you use single STP or you use the default configuration of a separate spanning tree for each port-based VLAN (multiple-instance STP).
You can configure the following parameters on the global level. The parameters apply to all ports.
•Forward Delay – The period of time a bridge will wait (the listen and learn period) before forwarding data packets. Possible values: 4 – 30 seconds. Default is 15.
