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New Member

Portfast with BPDU Filter


I'm pretty new to setting up VOIP and do not understand configuring portfast on our access port.

For example, If a user or an IT person mistakenly plugs the same cable from the phone back into the other phone port or another port on the wall, will this cause a spanning tree loop?

I have looked into putting the ports in portfast this in the past, but this kept us back as a reference site we went to said they had trouble with this sort of thing?

The config I have setup on the access port is:

interface FastEthernet0/5

switchport mode access

switchport access vlan 9

switchport voice vlan 12

no ip address

spanning-tree portfast

mls qos trust cos

Please can you advise if this is at all an issue? Can someone explain ether way?

We are using Avaya 4600 and 96xx phone if that makes any difference?



Re: Portfast with BPDU Filter

hi there

first of all

portfast help u in the DHCP

because it let the port go to forwarding phase directly so can get an IP from the DHCP

about ur IP phones avaya deffeent from cisco config in some areas such as the TFTP so what i advice is to search the config the relate to avaya with cisco switch

thanks u

rate if helpful

New Member

Re: Portfast with BPDU Filter

Thanks for you advice. My only concern about enabling portfast is it turn will turn off STP on the port. Therefore could this cause a rooting loop if the phone port was mistakenly connected to another port?

Re: Portfast with BPDU Filter

in stp there is blocking, learning lesteing an forwarding stages

this command let the port go directly to forwarding state so it might make problem if u put it on interface connected to other switch

only enable it on access ports

hope this helpful