Spantree Path-Cost-Mode - Alcatel-Lucent 060321-10, Rev. B Cli Reference Manual

spantree path-cost-mode

spantree path-cost-mode
Configures the automatic selection of a 16-bit path cost for STP/RSTP ports and a 32-bit path cost for
MSTP ports or sets all path costs to use a 32-bit value.
spantree path-cost-mode {auto | 32bit}
Syntax Definitions
auto
32bit
Defaults
By default, the path cost mode is set to auto.
Platforms Supported
OmniSwitch 10K
Usage Guidelines
•
All path cost values, except those for MSTIs, are reset to the default path cost value when this mode is
changed.
•
When connecting a switch running in the 32-bit path cost mode to a switch running in the 16-bit mode,
the 32-bit switch has a higher path cost value and thus an inferior path cost to the 16-bit switch. To
avoid this, use the spantree path-cost-mode command to change the 32-bit switch to a 16-bit switch.
•
Note that when the 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 exception to this is if the path cost
mode is set to 32-bit prior to the protocol change, the path cost is not reset to its default value
Examples
-> spantree path-cost-mode 32bit
-> spantree path-cost-mode auto
Release History
Release 7.1.1; command introduced.
Related Commands
spantree protocol
page 5-28
The port path cost value is automatically set depending on which
protocol is active on the switch (32-bit for MSTP, 16-bit for STP/
RSTP).
Specifies that a 32-bit value is used for the port path cost value
regardless of which protocol is active on the switch.
Configures the protocol for the flat mode CIST instance or a per-VLAN
mode VLAN instance.
Distributed Spanning Tree Commands
OmniSwitch CLI Reference Guide March 2011