The switch software uses the IEEE 802.1d Spanning Tree Protocol (STP). If RSTP/MSTP is turned on, see the “Rapid Spanning Tree information” section for Spanning Tree Group information. In addition to seeing if STP is enabled or disabled, you can view the following STP bridge information:
•Status of Uplink Fast (upfast)
•Current root MAC address
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•Port
•Hello interval
•Maximum age value
•Forwarding delay
•Aging time
You can also refer to the following
•Port number and priority
•Cost
•State
•Port Fast Forwarding state
•Designated bridge
•Designated port
The following table describes the STP parameters.
Table 22 STP parameters
Parameter | Description | |
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Current Root | Shows information about the root bridge for the Spanning Tree. Information includes the | |
| priority (hex) and MAC address of the root. | |
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| between bridges (up to the root bridge). | |
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Port | The current root port refers to the port on the switch that receives data from the current | |
| root. Zero (0) indicates the root bridge of the STP. | |
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Priority (bridge) | The bridge priority parameter controls which bridge on the network will become the STP | |
| root bridge. | |
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Hello | The hello time parameter specifies, in seconds, how often the root bridge transmits a | |
| configuration bridge protocol data unit (BPDU). Any bridge that is not the root bridge | |
| uses the root bridge hello value. | |
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MaxAge | The maximum age parameter specifies, in seconds, the maximum time the bridge waits | |
| without receiving a configuration bridge protocol data unit before it reconfigures the STP | |
| network. If the bridge is not the root bridge, it uses the MaxAge value of the root bridge. | |
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FwdDel | The forward delay parameter specifies, in seconds, the amount of time that a bridge port | |
| has to wait before it changes from learning state to forwarding state. If the bridge is not | |
| the root bridge, it uses the FwdDel value of the root bridge. | |
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Aging | The aging time parameter specifies, in seconds, the amount of time the bridge waits | |
| without receiving a packet from a station before removing the station from the Forwarding | |
| Database. | |
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Priority (port) | The port priority parameter helps determine which bridge port becomes the designated | |
| port. In a network topology that has multiple bridge ports connected to a single segment, | |
| the port with the lowest port priority becomes the designated port for the segment. | |
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Cost | The port path cost parameter is used to help determine the designated port for a segment. | |
| Generally speaking, the faster the port, the lower the path cost. | |
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State | The State field shows the current state of the port. The State field can be one of the | |
| following: BLOCKING, LISTENING, LEARNING, FORWARDING, or DISABLED. | |
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Designated bridge | Shows information about the bridge connected to each port, if applicable. Information | |
| includes the priority (hex) and MAC address of the Designated Bridge. | |
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| Information Menu 38 |