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spanning tree timers

Hi all, can anyone tell me what spanning tree timers are used for, and at what point in a network will you start to have spanning tree issues, is it anything after 7 uplinked switches ?


Re: spanning tree timers

Carl, referen the links bellow to get a good understanding on the industry standard STP ( 802.1D project ),

this is a very extensive question. once understood you will see a better picture down the road on other types of Cisco proprietary

Spanning tree versions and flavors.. but stp is basically a link management protocol, as well as used to prevent bridging loops in a network. See bridging loop links bellow for details. Link management is where dual paths exists from one switch to another

to provide link redundancy.

STP as Layer 2 protocol

STP timers, go through this document which can explain in more details the scope ot STP timers, STP timer values are set by default , however, values can be changed to obtain faster STP converging in its management throughout the stp topology.

STP should be used on two or more catalyst switchs.

Configuring and Building spanning tree topology

Your question on " When will networks start seeing Spanning tree issues " I think you are referring to bridging loops. The concept of spanning tree issues or spanning tree loops has been missed used for years, it should be instead bridging loops issues, in any case, here is when STP protocol comes in place to prevent these loops and ease our lives.

refer to this link for understanding bridging loops in a network.