Question { 14366 }

Can anyone explain in details port fast, uplink fast &
backbone fast features introduced by CISCO (The GOD FATHER
of NETWORKING.... Hehehehehe).

Answer

Port Fast :- Port fast is a feature which will make a
switchport comes directly in the Forwarding state instead
of waiting 60 sec and processing every state of
(Blocking,Listining,Learning) before coming in the
forwarding state. Recomended to enable on the Access ports
only.

Uplink Fast :- suppose When a switch has two paths to reach
the root bridge then by default one of the uplink will be
disabled by the STP, and if the active uplink goes down
then the secondary link will take 60 sec to comes in the
active state and we cannot run portfast in this situation,
so to reduce this dealy. we use uplink fast. uplink fast
feature is enable golobally not on the port basis as
portfast

Backbone fast :- Backbone fast feature is used to indirect
link failures to the root bridge/switch. Backbone fast
feature uses the Root link query protocol to detect
indirect link failures. Backbone fast feature is enabled
globally and has to be enable on all the switches in the
network.


Hope this will help !!!!