Spanning Tree Commands
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4
spanning-tree portfast
This command sets an interface to fast forwarding. Use the no form to disable fast
forwarding.
Syntax
[no] spanning-tree portfast
Default Setting
Disabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• This command is used to enable/disable the fast spanning-tree mode for the
selected port. In this mode, ports skip the Discarding and Learning states, and
proceed straight to Forwarding.
• Since end-nodes cannot cause forwarding loops, they can be passed through
the spanning tree state changes more quickly than allowed by standard
convergence time. Fast forwarding can achieve quicker convergence for
end-node workstations and servers, and also overcome other STA related
timeout problems. (Remember that fast forwarding should only be enabled for
ports connected to a LAN segment that is at the end of a bridged LAN or for
an end-node device.)
• This command is the same as spanning-tree edge-port, and is only included
for backward compatibility with earlier products. Note that this command may
be removed for future software versions.
Example
Related Commands
spanning-tree edge-port (4-172)
spanning-tree link-type
This command configures the link type for Rapid Spanning Tree and Multiple
Spanning Tree. Use the no form to restore the default.
Syntax
spanning-tree link-type {auto | point-to-point | shared}
no spanning-tree link-type
• auto - Automatically derived from the duplex mode setting.
• point-to-point - Point-to-point link.
• shared - Shared medium.
Console(config)#interface ethernet 1/5
Console(config-if)#bridge-group 1 portfast
Console(config-if)#