Alcatel-Lucent 6850-48 Reference Guide
Distributed Spanning Tree Commands
OmniSwitch CLI Reference Guide
September 2009
page 15-63
bridge msti slot/port priority
Configures the Spanning Tree priority value for a port or an aggregate of ports for the specified flat mode
Multiple Spanning Tree Instance (MSTI). The Spanning Tree algorithm uses the port priority value to
determine the most favorable port when a bridge has multiple ports with the same path cost to the root
bridge.
Multiple Spanning Tree Instance (MSTI). The Spanning Tree algorithm uses the port priority value to
determine the most favorable port when a bridge has multiple ports with the same path cost to the root
bridge.
bridge msti msti_id {slot/port | logical_port} priority priority
Syntax Definitions
msti_id
An existing MSTI ID number (0–4094).
slot/port
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).
that module (e.g., 3/1 specifies port 1 on slot 3).
logical_port
Link aggregate ID number (0–31).
priority
Port priority value (0–15). The lower the number, the higher the
priority.
priority.
Defaults
By default, the bridge port priority value is set to 7.
Platforms Supported
OmniSwitch 6400, 6850, 6855, 9000, 9000E
Usage Guidelines
• The port priority specifies the value of the priority field contained in the first byte of the Port ID. The
second byte contains the physical switch port number.
• 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 port priority value for any MSTI is not configurable in either mode.
mode protocol, however, the port priority value for any MSTI is not configurable in either mode.
• Note that if zero is entered for the msti_id value, the specified priority value is applied to the CIST
instance. The flat mode CIST instance 0 is also known as MSTI 0.
• The port priority value configured with this command is only applied to the specified MSTI. As a
result, a single port can have different priority values for each instance. For example, in flat mode, port
1/24 can have a priority value of 7 for MSTI 2 and a priority value of 5 for MSTI 3.
1/24 can have a priority value of 7 for MSTI 2 and a priority value of 5 for MSTI 3.
• If the switch is running in 1x1 mode when this command is used, the specified priority 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.