HP 9304m Installation And Getting Started Manual page 180

If you add a port that is the primary port of a trunk group, all ports in the trunk group become members of the Fast
Uplink Span group.
You can add ports to a Fast Uplink Span group by entering the fast uplink-span command additional times with
additional ports. The device can have only one Fast Uplink Span group, so all the ports you identify as Fast Uplink
Span ports are members of the same group.
To remove a Fast Uplink Span group or to remove individual ports from a group, use "no" in front of the appropriate
fast uplink-span command. 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 (SSTP)
By default, each port-based VLAN on an HP device runs a separate spanning tree, which you can enable or
disable on an individual VLAN basis.
Alternatively, you can configure an HP device to run a single spanning tree across all ports and VLANs on the
device. The Single STP feature (SSTP) is especially useful for connecting an HP device to third-party devices that
run a single spanning tree in accordance with the 802.1q specification.
SSTP uses the same parameters, with the same value ranges and defaults, as the default STP support on HP
devices. See "STP Parameters and Defaults" on page 6-2.
NOTE: If you are considering enabling single STP on the HP device in order to interoperate with Cisco devices
that are running PVST/PVST+, use PVST or PVST+ on the Cisco devices and use HP's PVST support instead.
The PVST/PVST+ support is automatically enabled in PVST/PVST+ environments and does not require any
configuration changes. Using PVST+ and enabling single STP on the HP device can require STP configuration
changes and is less flexible for load balancing using STP.
SSTP Defaults
SSTP is disabled by default. When you enable the feature, all VLANs on which STP is enabled become members
of a single spanning tree. All VLANs on which STP is disabled are excluded from the single spanning tree.
• To add a VLAN to the single spanning tree, enable STP on that VLAN.
• To remove a VLAN from the single spanning tree, disable STP on that VLAN.
When you enable SSTP, all the ports that are in port-based VLANs with STP enabled 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 SSTP 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 SSTP while still using your existing VLAN configurations
without changing your network. In addition, SSTP does not affect 802.1q tagging. Tagged and untagged ports
alike can be members of the single spanning tree domain.
NOTE: When SSTP is enabled, the BPDUs on tagged ports go out untagged.
If you disable SSTP, all VLANs that were members of the single spanning tree run MSTP instead. In MSTP, each
VLAN has its own spanning tree. VLANs that were not members of the single spanning tree were not enabled for
STP. Therefore, STP remains disabled on those VLANs.
Enabling SSTP
To enable SSTP, use one of the following methods.
Configuring Spanning Tree Protocol (STP)
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