PVSTP question

Hi,
What will happen if on one switch we have PVSTP+ implemented(cisco switch) and on the other we have only STP(non cisco switch).
I think that the PVSTP will only communicate on VLAN 1. Any ideas ? Hints?

I MEANT PVSTP+, sorry could not change the Topic neam

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chmorin

NullCode wrote: »

Hi,
What will happen if on one switch we have PVSTP+ implemented(cisco switch) and on the other we have only STP(non cisco switch).
I think that the PVSTP will only communicate on VLAN 1. Any ideas ? Hints?

I MEANT PVSTP+, sorry could not change the Topic neam

This is one of those questions where we could tell you, but most people would (hopefully) agree when I say go lab it up! I'm not trying to be mean, but this is how you learn:

What do you think will happen?
Why do you think that will happen?
-Lab-
What actually happened?
Why did that happen?
Were you correct?

Let us know

NullCode

chmorin wrote: »

What do you think will happen?
Why do you think that will happen?
-Lab-
What actually happened?
Why did that happen?
Were you correct?

Let us know

I am interested in the theory not in the actual output.

chmorin

NullCode wrote: »

I am interested in the theory not in the actual output.

The two go hand in hand. I honestly don't see a point in learning anything if I can't use it. I also don't see a point in learning how to use something if I don't know what it is doing.

Well - I labbed it and came to this conclusion:

Lab:

When I had them all using STP using VLAN 1 with an IP address, all switches could ping each other.

When I changed the two edge switches to pvstp but still using vlan 1, all switches could ping each other.

When I change all switches to shut vlan 1, and use vlan 10, the two edge switches running pvstp could ping each other, but not the middle switch.

So it would be safe to say if you keep an stp switch connected to a pvstp switch, only VLAN 1 can be used by default with the stp switch.