Some troubleshooting activity may require you to identify the root-switch or root bridge in a spanning-tree environment. To identify the root bridge or tweak the root bridge election, you would need to understand the role of priority first. The bridge priority is used to control which bridge is elected as the root bridge and also to control which bridge is elected as the root bridge when the initial root bridge fails. The bridge priority determines which bridge is elected as the root bridge. If two bridges have the same path cost to the root bridge, the bridge priority determines which bridge becomes the designated bridge for a LAN segment. The root bridge in a spanning-tree network is the bridge with the smallest or the lowest bridge ID. This can be verified by issuing the following command. Switch@juniper>show spanning-tree bridge STP bridge parameters Context ID : 0 Enabled protocol : RSTP Root ID : 32768.28:c0:da:3d:50:40
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