Hirschmann RS20 User Manual page 65

Spanning Tree

If there are multiple paths with the same root path costs, the bridge further
away from the root decides which port it blocks. For this purpose, it uses
the bridge identifiers of the bridge closer to the root. The bridge blocks the
port that leads to the bridge with the numerically higher ID (a numerically
higher ID is the logically worse one). If 2 bridges have the same priority,
the bridge with the numerically larger MAC address has the numerically
higher ID, which is logically the worse one.
 If multiple paths with the same root path costs lead from one bridge to the
same bridge, the bridge further removed from the root uses the port
identifier of the other bridge as the last criterion
process, the bridge blocks the port that leads to the port with the
numerically higher ID (a numerically higher ID is the logically worse one).
If 2 ports have the same priority, the port with the higher port number has
the numerically higher ID, which is logically the worse one.
UM Redundancy Configuration L2E
Release 7.1 12/2011
5.2 Rules for Creating the Tree
(see fig. 30). In the
Structure
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