Pilz PSSnet SHL 8T MRP - Manual (Page 61)

Rapid Spanning Tree
PSSnet SHL - Redundancy Configuration
Pilz GmbH & Co. KG, Felix- Wankel Str. 2, 73760 Ostfildern
4.3 Example of specifying the root
paths
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4.3 Example of specifying the
root paths
The network plan (see fig. 32) can be used to create the flow diagram (see
fig. 31) for defining the root path. The Administrator defined a different priority
in the bridge identifier for each bridge. The bridge with the smallest number
for the bridge identifier is the root bridge, in this case bridge 1. In the
example, all the sub-paths have the same path costs. The path between
bridge 2 and bridge 3 is interrupted, because a connection from bridge 3 to
the root bridge via bridge 2 would double the path costs.
The path from bridge 6 to the root bridge is interesting:
X The path via bridge 5 and bridge 3 creates the same root path costs as
the path via bridge 4 and bridge 2.
X The path via bridge 4 is selected because value 28 672 for the priority in
the bridge identifier is smaller than value 32 768.
X However, there are two paths between bridge 6 and bridge 4. The port
identifier is decisive here.