
FL SWITCH MM HS(Rapid) Spanning Tree
6874_en_16
PHOENIX CONTACT
5-23
5.2.5.6
Flowchart for specifying the root path
Figure 5-17
Flowchart for specifying the root path
5.2.5.7
Extended configuration
It may be useful to actively specify the topology that is formed due to the Spanning Tree
Protocol and to not leave it to the random MAC addresses of the switches involved.
Non-blocking/blocking data paths can thus be influenced and a load distribution specified.
It may also be useful to explicitly disable the Spanning Tree Protocol at ports that do not
participate in Spanning Tree so as to benefit from the fast forwarding function.
The Spanning Tree Protocol must also be disabled at individual ports if two different network
segments - both using Spanning Tree - are to be coupled via these ports without the two tree
structures merging into a large Spanning Tree.
Specifying the root switch
The root switch is assigned via the assignment of an appropriate priority for the Spanning
Tree segment. Set the highest priority (lowest value) in the "Priority" field on the "STP Bridge
Configuration" page in WBM for the switch selected as the root switch. Make sure that all
Determine path
to root switch
Same
path costs?
Same priority for switches
(bridge identification)?
Same priority for
individual ports?
Lowest path costs
Root path
Highest priority for switch
Root path
Highest priority for port
Root path
Lowest port number
Root path
Path to root
switch is determined
Yes
Yes
Yes
No
No
No
RSPSupply - 1-888-532-2706 - www.RSPSupply.com
http://www.RSPSupply.com/p-14178-Phoenix-Contact-2832357-FL-IF-2TX-VS-RJ-D-Media-Module-for-Modular-Switch.aspx