Mixing of STP awared and unawared switches

Hi guys!
I have 4 switches in my network topology.
3 of them have STP running and the other one has STP disabled.
I would like to know how that STP unawared switch will be treated?
What will happen if I shutdown or remove that STP unawared switch?
Will it affect the convergence time of STP?

Hello Alex

When STP enabled switches are connected, they become aware of each other and of the whole STP functionality by the exchanging of BPDUs. If a switch has STP disabled, it will not send out any BPDUs. It will receive them from the STP enabled switches, but it will disregard them completely. So the STP enabled switches will not detect the STP disabled switch on the ports that connect them. Convergence would occur as if the switch wasn’t even there.

If the switch is shutdown or removed, absolutely nothing will change in the topology and state of the STP convergence of the remaining switches.

Now if a loop does occur that involves this STP disabled switch, then there will indeed be a network malfunction; even this will not affect the currently converged STP environment.

I hope this has been helpful!


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Thanks Laz.
It helps!

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