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Spanning tree portfast

Our client has many remote sites in different location and each site is with a WAN router and a 3750 X switch. Switch is working as a layer 3 switch and the uplink connected to WAN router is a layer 3 interface. They have configuered " Spanning tree portfast" on the uplink going to WAN router. Is that required to configure "spanning tree portfast" over that uplink to WAN router?

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Spanning tree portfast

Spanning tree  Portfast should be enabled on ports connecting to hosts (PCs, laptops, printers, etc...) your uplink port is routed port, so there is no STP involved.

HTH

Re: Spanning tree portfast

Hi,

there's no possibility for the occurrence of a bridging-loop between the router and the switch, so it's safe to configure portfast.

Without portfast, after re-initialization the link, no traffic would be forwarded for 30 seconds (2x forward delay), so from a convergence perspective this is a meaningful optimization.

in case of a routed port, STP portfast makes no sense (I've overlooked that, sorry).

Hope that helps

Rolf

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