port flapping in STP domain

[N.ima0102]

Hi

If one port is flapping for every one minute (up down) ,what's happened for switches of STP domain?

Does this flapping effect on whole STP switches?May this flapping totally down STP domain?

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[sukanyachavan]

Hii,

STP domain will be affected due to port flapping.Spanning tree will converge everytime the port flaps.

HTH,

Sukanya

PS: Please rate helpful posts...

[Sandeep Choudhary]

HI Nima,

1. It is alwayes better to use to use AutoNegotiation on GigaPorts.

2.Port Flapping can affect latency if the ports are part of the transit flow

3. It also causes STP to recalculate if running Layer2 services on those ports or a routing protocol to converge if running Layer3 services along with dynamic routing

4. All these issues will affect switch performance.

I will try to find about the effect on stp domain.

Regards

please rate if it helps.

[jimmysands73_2]

Your going to confuse Nima....

If portfast is enabled on the flapping port, port flapping has no effect (no TCN is generated).  You can slap the port when it flaps, but that doesnt always work

See

Understanding Spanning-Tree Protocol Topology Changes

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a0080094797.shtml