Siemens SIMATIC NET SCALANCE S615 Configuration Manual page 104

Configuring with Web Based Management
4.4 "Information" menu
Description of the displayed values
The following fields are displayed:
● Spanning Tree Mode
Shows the set mode. You specify the mode in "Layer 2 > Configuration" and in "Layer 2 >
Spanning Tree > General".
The following values are possible:
– '-'
– RSTP
● Bridge Priority / Root Priority
Which device becomes the root bridge is decided by the bridge priority. The bridge with the
highest priority (in other words, with the lowest value for this parameter) becomes the root
bridge. If several devices in a network have the same priority, the device whose MAC
address has the lowest numeric value will become the root bridge. Both parameters, bridge
priority and MAC address together form the bridge identifier. Since the root bridge manages
all path changes, it should be located as centrally as possible due to the delay of the frames.
The value for the bridge priority is a whole multiple of 4096 with a range of values from 0 to
32768.
● Bridge Address / Root Address
The bridge address shows the MAC address of the device and the root address shows the
MAC address of the root switch.
● Root Cost
Shows the path costs from the device to the root bridge.
● Bridge Status
Shows the status of the bridge, e.g. whether or not the device is the root bridge.
The table has the following columns:
● Port
Shows the interfaces via which the device communicates.
● Role
Shows the status of the port. The following values are possible:
– Disabled
– Designated
– Alternate
– Backup
– Root
– Master
104
The port was removed manually from the spanning tree and will no longer be taken into
account by the spanning tree.
The ports leading away from the root bridge.
The port with an alternative route to a network segment
If a switch has several ports to the same network segment, the "poorer" Port becomes
the backup port.
The port that provides the best route to the root bridge.
This port points to a root bridge located outside the MST region.
SCALANCE S615 Web Based Management
Configuration Manual, 11/2019, C79000-G8976-C388-08