spanning tree portfast

[ARMANDO ALVARADO]

Question to make sure I understand this correctly.

I know when using spanning tree portfast on host ports should be enabled. But what about when using trunked portchannels and non trunk portchannels and a truncked port in general. A little misguided here just want to clear the air. Thanks

[fgasimzade]

This is what Cisco says:

PortFast should be used only

when connecting a single end station to a switch port. If you enable  PortFast on a port connected to another networking device, such as a  switch, you can create network loops.

[Jon Marshall]

There is an option you can configure on a trunk link ie. "spanning-tree portfast trunk" and this may be what you are referring to.

On no account should this be used on trunk links between switches. Where you may want to use it is when you have a server that is 802.1q capable and running a trunk to the switch. Running portfast on this trunk link is unlikely to create a loop in your network and would allow the server to begin forwarding immediately rather than having to wait as it goes through the STP calculation.

Jon