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MSTP convergence

Hi All

I am looking at issues with convergence on ring of 3550 / 3750.

What is the limit of switches that can be put on a ring topology ? I am not sure but my issues seems to be related to number of trunks, each time I add a trunk convergence times increases.

Any thoughts....before I segment the ring.

As a side mote, looking after this issues has cost me the nickname of Frodo Baggins.

TIA

Cisco Lad

2 REPLIES
VIP Purple

Re: MSTP convergence

Hello,

AFAIR, Frodo Baggins eventually destroyed the big bad Sauron and saved the world ? So that nickname does not sound too bad, I'd say...

When you say 'ring', does that mean your topology looks like this ?

Swicth1 --> Switch2 --> Switch3 --> Switch4 --> Switch1

In general, the maximum spanning tree diameter, as defined by the IEEE, is seven, how many switches do you have ? Can you maybe draw out your physical setup and post it here ?

Regards,

GP

Re: MSTP convergence

Hey Georg

Long time, no speak.

7 switches only applies to STP, I am running MSTP and I think the limitation is 20. I currently have 16 in total. I can of course change the timers, but do not dare as all state bodies and high end corporate are serviced on this metro ring.

Tia

Sam

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