Bridge Msti Slot/Port Path Cost - Alcatel-Lucent OmniSwitch 6250 Cli Reference Manual

Distributed Spanning Tree Commands

bridge msti slot/port path cost

Configures the Spanning Tree path cost value for a port or an aggregate of ports for the specified flat
mode Multiple Spanning Tree Instance (MSTI). This value is the contribution of this port to the path cost
towards the Spanning Tree root bridge that includes this port. Path cost is a measure of the distance of the
listed port from the root bridge in the number of hops.
bridge mist msti_id {slot/port | logical_port} path cost path_cost
Syntax Definitions
msti_id
slot/port
logical_port
path_cost
Defaults
By default, the path cost is set to zero.
Platforms Supported
OmniSwitch 6250
Usage Guidelines
•
This command is an explicit Spanning Tree command that only applies to the specified MSTI regard-
less of which operating mode (flat or 1x1) is active on the switch. If MSTP is not the selected flat
mode protocol, however, the path cost value for any MSTI is not configurable.
•
Note that if zero is entered for the msti_id value, the specified path cost value is applied to the CIST
instance. The flat mode CIST instance 0 is also known as MSTI 0.
•
Note that when the Spanning Tree protocol is changed to/from MSTP, the bridge priority and port path
cost values for the flat mode CIST instance are reset to their default values.
•
The path cost value configured with this command is only applied to the specified instance. As a result,
a single port can have a different path cost for each instance. For example, in flat mode, port 1/24 can
have a path cost of 20000 for MSTI 2 and a path cost of 200000 for MSTI 3.
•
If the switch is running in 1x1 mode when this command is used, the specified path cost value is not
active for the specified MSTI until the operating mode for the switch is changed to the flat mode.
•
Note that when a configuration snapshot is taken of the switch, all Spanning Tree commands are saved
in their explicit format.
•
When MSTP is the active protocol on the switch, only a 32-bit path cost value is used. Using a 16-bit
path cost value is not an option.
•
If zero is entered for the path_cost value, then the following recommended default path cost values
based on link speed are used:
OmniSwitch 6250 CLI Reference Guide
An existing MSTI ID number (0–4094).
Enter the slot number for the module and the physical port number on
that module (e.g., 3/1 specifies port 1 on slot 3).
Link aggregate ID number (0–31).
Path cost value (0 - 65535 for 16-bit, 0–200000000 for 32-bit).
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