Spanning Tree Commands 4

Command Usage

This command sets the maximum time (in seconds) the root device will wait before changing states (i.e., discarding to learning to forwarding). This delay is required because every device must receive information about topology changes before it starts to forward frames. In addition, each port needs time to listen for conflicting information that would make it return to the discarding state; otherwise, temporary data loops might result.

Example

Console(config)#spanning-tree forward-time 20

Console(config)#

spanning-tree hello-time

This command configures the spanning tree bridge hello time globally for this switch. Use the no form to restore the default.

Syntax

spanning-tree hello-time time no spanning-tree hello-time

time - Time in seconds. (Range: 1-10 seconds).

The maximum value is the lower of 10 or [(max-age / 2) -1].

Default Setting

2 seconds

Command Mode

Global Configuration

Command Usage

This command sets the time interval (in seconds) at which the root device transmits a configuration message.

Example

Console(config)#spanning-tree hello-time 5

Console(config)#

spanning-tree max-age

This command configures the spanning tree bridge maximum age globally for this switch. Use the no form to restore the default.

Syntax

spanning-tree max-age seconds no spanning-tree max-age

seconds - Time in seconds. (Range: 6-40 seconds)

The minimum value is the higher of 6 or [2 x (hello-time + 1)]. The maximum value is the lower of 40 or [2 x (forward-time - 1)].

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