Fast Uplink Span - HP ProCurve 9304M Installation And Configuration Manual

HP9300(config)# write memory
Syntax: [no] fast port-span [exclude ethernet <portnum> [ethernet <portnum>... | to <portnum>]]
To re-enable Fast Port Span on a port, enter a command such as the following:
HP9300(config)# no fast port-span exclude ethernet 1/1
HP9300(config)# write memory
This command re-enables Fast Port Span on port 1/1 only and does not re-enable Fast Port Span on other
excluded ports. You also can re-enable Fast Port Span on a list or range of ports using the syntax shown above
this example.
To re-enable Fast Port Span on all excluded ports, disable and then re-enable Fast Port Span by entering the
following commands:
HP9300(config)# no fast port-span
HP9300(config)# fast port-span
HP9300(config)# write memory
Disabling and then re-enabling Fast Port Span clears the exclude settings and thus enables Fast Port Span on all
eligible ports. To make sure Fast Port Span remains enabled on the ports following a system reset, save the
configuration changes to the startup-config file after you re-enable Fast Port Span. Otherwise, when the system
resets, those ports will again be excluded from Fast Port Span.
USING THE WEB MANAGEMENT INTERFACE
You cannot exclude individual ports from Fast Span using the Web management interface.

Fast Uplink Span

The Fast Port Span feature described in the previous section enhances STP performance for end stations. The
Fast Uplink feature enhances STP performance for wiring closet switches with redundant uplinks. Using the
default value for the standard STP forward delay, convergence following a transition from an active link to a
redundant link can take 30 seconds (15 seconds for listening and an additional 15 seconds for learning).
You can use the Fast Uplink feature on an HP device deployed as a wiring closet switch to decrease the
convergence time for the uplink ports to another device to just four seconds (two seconds for listening and two
seconds for learning). The wiring closet switch must be an HP device but the device at the other end of the link
can be an HP device or another vendor's switch. Configuration of the Fast Uplink Span feature takes place
entirely on the HP device.
To configure the Fast Uplink Span feature, specify a group of ports that have redundant uplinks on the wiring
closet switch (HP device) as members of a Fast Uplink Group. If the active link becomes unavailable, the Fast
Uplink Span feature transitions the forwarding to one of the other ports in four seconds. You can configure one
Fast Uplink Span group on the device. All Fast Uplink Span ports are members of the same Fast Uplink Span
group.
NOTE: To avoid the potential for temporary bridging loops, Hewlett-Packard recommends that you use the Fast
Uplink feature only for wiring closet switches (switches at the edge of the network cloud). In addition, enable the
feature only on a group of ports intended for redundancy, so that at any given time only one of the ports is
expected to be in the forwarding state.
Fast Uplink Span Rules for Trunk Groups
If you add a port to a Fast Uplink Span group that is a member of a trunk group, the following rules apply:
• If you add the primary port of a trunk group to the Fast Uplink Span group, all other ports in the trunk group
are automatically included in the group. Similarly, if you remove the primary port in a trunk group from the
Fast Uplink Span group, the other ports in the trunk group are automatically removed from the Fast Uplink
Span group.
• You cannot add a subset of the ports in a trunk group to the Fast Uplink Span group. All ports in a trunk group
have the same Fast Uplink Span property, as they do for other port properties.
Configuring Spanning Tree Protocol (STP) and Advanced STP Features
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