HP procurve 2500 Benutzerhandbuch

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Enhancements in Release F.02.11
Fast-Uplink Spanning Tree Protocol (STP)
To use fast-uplink STP on a Series 2500 switch, configure fast-uplink (
Mode
 = 
Uplink
) only on the 
switch’s upstream ports; (that is, two or more ports forming a group of redundant links in the direction 
of the STP root switch). If the active link in this group goes down, fast-uplink STP selects a different 
upstream port as the root port and resumes moving traffic in as little as ten seconds. The device(s) 
on the other end of the links must be running STP. However, because fast uplink should be configured 
only on the Series 2500 switch uplink ports, the device(s) on the other end of the links can be either 
HP devices or another vendor’s devices, regardless of whether they support fast uplink. For example:
Figure 67.   Example of How To Implement Fast-Uplink STP
Terminology
Term
Definition
downlink port
(downstream port)
A switch port that is linked to a port on another switch (or to an end node) that is sequentially 
further away from the STP root device. For example, port "C" in figure 67, above,  is a downlink 
port.
edge switch
For the purposes of fast-uplink STP, this is a switch that has no other switches connected to 
its downlink ports. An edge switch is sequentially further from the root device than other 
switches to which it is connected. Also termed wiring closet switch or leaf switch. For 
example, switch "4" in figure 68 (page 150) is an edge switch.
interior switch
In an STP environment, a switch that is sequentially closer to the STP root device than one 
or more other switches to which it is connected. For example, switches "1",  "2", and "3"  in 
figure 68 (page 150) are interior switches.
single-instance spanning 
tree
A single spanning-tree ensuring that there are no logical network loops associated with any 
of the connections to the switch, regardless of whether there are any VLANs configured on 
the switch. For more information, see "Spanning Tree Protocol (STP)" in chapter 9, "Configuring 
Advanced Features", in the Management and Configuration Guide for your Series 2500 switch.
uplink port
(upstream port)
A switch port linked to a port on another switch that is sequentially closer to the STP root 
device. For example, ports "A" and "B" in figure 67 on page 149 are uplink ports.
wiring closet switch
Another term for an "edge" or "leaf" switch.
STP is running on both switches.
Port "A" and port "B" are both configured for 
fast-uplink STP (Mode = Uplink).
STP Root Switch
Series 2500
Switch
(Wiring Closet, 
or Edge 
Switch)
LAN
STP Blocking
     Port A is the STP root port.
B
Port B provides a backup redundant link. 
that becomes the new STP root port 
(uplink port) if the link through port A fails.
C
A
D
E