02-02-2019 06:13 PM - edited 03-08-2019 05:13 PM
My understanding is that by default, PortFast is disabled on all switch ports and you can configure PortFast in two ways: per port and globally.
If you configure PortFast globally, all ports that are operational as access ports automatically become PortFast enabled and if they receive a BPDU, they will go into blocking mode.
If you configure PortFast on a port, the port will become PortFast enabled.
My question is, what happens when a BPDU is received on a port which has been enabled with PortFast under interface and not globally. Does the port go into blocking state, same like when PortFast is enabled globally?
Thanks
Syed
02-02-2019 07:22 PM
02-04-2019 05:00 AM
ngkin2010,
That is actually incorrect. Enabling portfast on an interface doesn't disable spanning tree on it. If a port with portfast enabled receives a BPDU it will process it as normal. The difference between portfast-enabled port and non-portfast-enabled is that portfast-enabled port skips listening and learning states and goes straight to forwarding.
02-04-2019 07:02 AM
02-03-2019 02:27 AM
Hi,
Please check below link - good post by Daniel Dib. Hopefully, it will answer your question.
http://lostintransit.se/2013/08/04/busting-myths-spanning-tree-portfast-on-the-interface/
02-03-2019 10:19 AM
Hello
Portfast applied either global or interface - will go from blocking and then bypass listen/learn (pvst+) states or from discarding and Learning states (Rpvst+/mst) and go into forwarding.
02-04-2019 07:22 AM
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