SMC Networks 8728L2 - annexe 1, Management Manual

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S
PANNING
T
REE
C
OMMANDS
4-199
Syntax
spanning-tree mst instance_id cost cost
no spanning-tree mst instance_id cost
• instance_id - Instance identifier of the spanning tree.
(Range: 0-4094, no leading zeroes)
• cost - Path cost for an interface. (Range: 1-200,000,000)
The recommended range is -
- Ethernet: 200,000-20,000,000
- Fast Ethernet: 20,000-2,000,000
- Gigabit Ethernet: 2,000-200,000
Default Setting
By default, the system automatically detects the speed and duplex mode
used on each port, and configures the path cost according to the values
shown below. Path cost “0” is used to indicate auto-configuration
mode.
• Ethernet – half duplex: 2,000,000; full duplex: 1,000,000; trunk:
500,000
• Fast Ethernet – half duplex: 200,000; full duplex: 100,000; trunk:
50,000
• Gigabit Ethernet – full duplex: 10,000; trunk: 5,000
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• Each spanning-tree instance is associated with a unique set of VLAN
IDs.
• This command is used by the multiple spanning-tree algorithm to
determine the best path between devices. Therefore, lower values
should be assigned to interfaces attached to faster media, and higher
values assigned to interfaces with slower media.
• Use the no spanning-tree mst cost command to specify
auto-configuration mode.
• Path cost takes precedence over interface priority.