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spanning-tree mode
This command selects the spanning tree mode for this switch. Use the no
form to restore the default.
Syntax
spanning-tree mode {stp | rstp}
no spanning-tree mode
• stp - Spanning Tree Protocol (IEEE 802.1D)
• rstp - Rapid Spanning Tree Protocol (IEEE 802.1w)
Default Setting
rstp
Command Mode
Global Configuration
Command Usage
• Spanning Tree Protocol
Uses RSTP for the internal state machine, but sends only 802.1D
BPDUs.
• Rapid Spanning Tree Protocol
RSTP supports connections to either STP or RSTP nodes by
monitoring the incoming protocol messages and dynamically
adjusting the type of protocol messages the RSTP node transmits, as
described below:
- STP Mode – If the switch receives an 802.1D BPDU after a port’s
migration delay timer expires, the switch assumes it is connected
to an 802.1D bridge and starts using only 802.1D BPDUs.
- RSTP Mode – If RSTP is using 802.1D BPDUs on a port and
receives an RSTP BPDU after the migration delay expires, RSTP
restarts the migration delay timer and begins using RSTP BPDUs
on that port.
Example
The following example configures the switch to use Rapid Spanning Tree:
Console(config)#spanning-tree mode rstp
Console(config)#