Hirschmann RS20 User Manual page 79

Spanning Tree
 Define the desired switch as the root bridge by assigning it the
lowest priority in the bridge information among all the bridges in the
network, in the "Protocol Configuration/Information" frame. Note that
only multiples of 4,096 can be entered for this value
In the "Root Information" frame, the dialog shows this device as the
root.
A root switch has no root port and a root cost of 0.
 If necessary, change the default priority value of 32,768 in other
bridges in the network in the same way to the value you want
(multiples of 4,096).
For each of these bridges, check the display
in the "Root Information" frame:
– Root-ID: Displays the root bridge's bridge identifier
– Root Port: Displays the port leading to the root bridge
– Root Cost: Displays the root cost to the root bridge
in the "Protocol Configuration/Information" frame:
– Priority: Displays the priority in the bridge identifier for this bridge
– MAC Address: Displays the MAC address of this Switch
– Topology Changes: Displays the number of changes since
the start of RSTP
– Time since last change: Displays the time that has elapsed since
the last network reconfiguration
 If necessary, change the values for "Hello Time", "Forward Delay"
and "Max. Age" on the rootbridge. The root bridge then transfers this
data to the other bridges. The dialog displays the data received from
the root bridge in the left column. In the right column you enter the
values which shall apply when this bridge becomes the root bridge.
For the configuration, take note of
UM Redundancy Configuration L2E
Release 7.1 12/2011
5.6 The Rapid Spanning Tree
table 13.
Protocol
(see table 13).
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