SMC Networks SMC8150L2 Configuring Global Settings, Global settings apply to the entire switch

Spanning Tree Algorithm Configuration 3

CLI – This command displays global STA settings, followed by settings for each port.

Console#show spanning-tree 4-160

Spanning-tree information

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Spanning tree mode:		RSTP
Spanning tree enabled/disabled:		enabled
Priority:	Time (sec.):	32768
Bridge Hello		2
Bridge Max Age (sec.):		20
Bridge Forward Delay (sec.):		15
Root Hello Time (sec.):		2
Root Max Age	(sec.):	20
Root Forward	Delay (sec.):	15
Designated Root:		32768.0012CF0B0D00
Current root	port:	0
Current root	cost:	0
Number of topology changes:		1
Last topology changes time (sec.):2262
Transmission	limit:	3
Path Cost Method:		long

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Note: The current root port and current root cost display as zero when this device is not connected to the network.

Configuring Global Settings

Global settings apply to the entire switch.

Command Usage

•Spanning Tree Protocol7

Uses RSTP for the internal state machine, but sends only 802.1D BPDUs. This creates one spanning tree instance for the entire network. If multiple VLANs are implemented on a network, the path between specific VLAN members may be inadvertently disabled to prevent network loops, thus isolating group members. When operating multiple VLANs, we recommend selecting the MSTP option.

•Rapid Spanning Tree Protocol7

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

7.STP and RSTP BPDUs are transmitted as untagged frames, and will cross any VLAN boundaries.

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