Spanning Tree
ROS™ v3.5 156 RS400
The Instance ID refers to the MSTI (Multiple Spanning Tree Instance) ID. Specify an Instance ID
and select GET in order to load parameters corresponding to the selected MSTI. Changes to
parameters that are subsequently applied will apply to the selected Instance ID. Note: Port
Parameters for the IST (MSTI zero), are accessible via the Port RSTP Parameters menu (see
section 5.4.2).
Port(s)
Synopsis: Any combination of numbers valid for this parameter
The port number as seen on the front plate silkscreen of the switch (or a list of ports, if
aggregated in a port trunk).
Priority
Synopsis: { 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 194, 208, 224, 240 }
Default: 128
Selects the STP port priority. Ports of the same cost that attach to a common LAN will select the
port to be used based on the port priority.
STP Cost
Synopsis: 0 to 65535 or { Auto }
Default: Auto
Selects the cost to use in cost calculations when the Cost Style parameter is set to STP in the
Bridge RSTP Parameters configuration. Setting the cost manually provides the ability to
preferentially select specific ports to carry traffic over others. Leave this field set to "auto" to use
the standard STP port costs as negotiated (4 for 1Gbps, 19 for 100 Mbps links and 100 for 10
Mbps links). For MSTP, this parameter applies to both external and internal path cost.
RSTP Cost
Synopsis: 0 to 2147483647 or { Auto }
Default: Auto
Selects the cost to use in cost calculations when the Cost Style parameter is set to RSTP in the
Bridge RSTP Parameters configuration. Setting the cost manually provides the ability to
preferentially select specific ports to carry traffic over others. Leave this field set to "auto" to use
the standard RSTP port costs as negotiated (20,000 for 1Gbps, 200,000 for 100 Mbps links and
2,000,000 for 10 Mbps links). For MSTP, this parameter applies to both external and internal
path cost.