SMC Networks SMC8748ML3 Management Manual page 226

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ONFIGURING THE
• 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 (i.e., STP
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.
• Multiple Spanning Tree Protocol
- To allow multiple spanning trees to operate over the network, you
must configure a related set of bridges with the same MSTP
configuration, allowing them to participate in a specific set of
spanning tree instances.
- A spanning tree instance can exist only on bridges that have
compatible VLAN instance assignments.
- Be careful when switching between spanning tree modes. Changing
modes stops all spanning-tree instances for the previous mode and
restarts the system in the new mode, temporarily disrupting user
traffic.
Command Attributes
Basic Configuration of Global Settings
• Spanning Tree State – Enables/disables STA on this switch.
(Default: Enabled)
• Spanning Tree Type – Specifies the type of spanning tree used on this
switch:
- STP: Spanning Tree Protocol (IEEE 802.1D); i.e., when this option
is selected, the switch will use RSTP set to STP forced compatibility
mode).
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WITCH