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New Member

All the client switches becoming STP ROOT switches

Hi All,

Here is my topology. I've two vlans (50,60). I was doing some lab so just build this topology and when i check the the spaning tree configuration on all the switches except the two transparent switches. All the client switches have become ROOT switches for VLAN50,60.

I've give the below commands on the VTP-Server, but still the problem is not clearing.

VTP-SERVER(config)#spanning-tree vlan 1 root primary

VTP-SERVER(config)#spanning-tree vlan 50 root primary

VTP-SERVER(config)#spanning-tree vlan 60 root primary

p1.PNG

"show spanning-tree" outputs:

Output from VTP-Server:

server.PNG

Output from Client1:

client1.PNG

Output from Client2:

client2.PNG

Output from Client3:

client3.PNG

Can someone please correct the issue?

Thanks in advance.

Regards,

Chandu

Regards, Chandu
Everyone's tags (2)
2 ACCEPTED SOLUTIONS

Accepted Solutions

Re: All the client switches becoming STP ROOT switches

Hi Chandu,

did you create VLANs 50 and 60 on the VTP transparent switches manually (as they won't be learned by VTP)?

Otherwise those VLANs will be partitioned as they simply don't exist on the intermediate switches.

HTH

Rolf

Re: All the client switches becoming STP ROOT switches

Without creating the required VLANs on the intermediate VTP transparent switches, you have 4 isolated local VLANs each for VLAN 50 and 60 without an interconnection ("the VLANs are partitioned"). The trunks on the transparent switches will not process frames tagged for VLANs they don't know.

5 REPLIES

Re: All the client switches becoming STP ROOT switches

Hi Chandu,

did you create VLANs 50 and 60 on the VTP transparent switches manually (as they won't be learned by VTP)?

Otherwise those VLANs will be partitioned as they simply don't exist on the intermediate switches.

HTH

Rolf

New Member

All the client switches becoming STP ROOT switches

No,

I didn't created VLANs 50,60 on vtp transparent switches... because the changes done on the domain will won't affect transparent switches and viceversa, right ?

So their duty is just to transfer the frames received on one trunk to other.

Regards,

Chandu

Regards, Chandu

Re: All the client switches becoming STP ROOT switches

Without creating the required VLANs on the intermediate VTP transparent switches, you have 4 isolated local VLANs each for VLAN 50 and 60 without an interconnection ("the VLANs are partitioned"). The trunks on the transparent switches will not process frames tagged for VLANs they don't know.

New Member

All the client switches becoming STP ROOT switches

Perfect - Rolf. Issue resolved.

I understood it. Since both the transparent switches are not having vlan50,60 they are not participating in the STP calculation for those two vlans.

Since those two switches are not participating in the STP calculation. For every switch it seems like it is the only switch in the topology, so STP made them ROOT switches, got it...

Really playing with devices like anything.... but however learning like this is very good...

Thanks a lot for your help again.

Regards,

Chandu

Regards, Chandu

Re: All the client switches becoming STP ROOT switches

Chando, thanks for the feedback.

I really enjoy watching your progress ;-)

Regards,

Rolf

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