EtherChannel, Spanning tree

[belsbree22]

Hi guys, I'm new to the community and networking in general. I am just learning about Etherchannels and STP, but had a question. 

I have set up two Etherchannels from say Switch one to Switch two, and also from Switch one to Switch three. 

They both say they are in use, although when I execute the "show spanning-tree" command, it will show Port-channel 1 (to the root bridge) in a root state, and Port-Channel 2 (Not to the root bridge) in a blocking state. 

That's all good, but my question arises when I see that the "show spanning-tree" command also shows me the physical interfaces that are being used in those port channels. 

For example, PO1 is using F0/23 - 24, and PO2 is using F0/21 - 22, and the command shows 23/24 (to the root bridge) in a forwarding state, but also 21/22  in a forwarding state as well. 21/22 are configured in the PO2, which should, I think be in a blocking state? Should it even show these physical interfaces at all, or did I do something wrong? 

Thanks for any help! 

[balaji.bandi]

Not sure until we see your diagram and output : 

take example I have a similar setup triangle connected (one of the branch) each other here s output show for vlan 300

[paul driver]

Hello

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@belsbree22 wrote:

when I see that the "show spanning-tree" command also shows me the physical interfaces that are being used in those port channels. 

For example, PO1 is using F0/23 - 24, and PO2 is using F0/21 - 22, and the command shows 23/24 (to the root bridge) in a forwarding state, but also 21/22  in a forwarding state as well. 21/22 are configured in the PO2, which should, I think be in a blocking state? Should it even show these physical interfaces at all, or did I do something wrong? 

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STP regards the PC relates to a single logical stp instance, so multiple PC are blocked based on the PC not the specific interfaced within the PC.

Are you using any aggregation protocol (pagp, lacp)

[belsbree22]

I forgot to attach these images of my show command outputs for reference. 

For instance, my outputs do not look like balaji's. 

[belsbree22]

Thank you guys for the replies, I figured out why it showed the Port channel interface and the physical interfaces on "show spanning-tree". 

It was because I didn't have those physical interfaces and the port channel interfaces with the same configuration. 

Thank you!

[balaji.bandi]

Glad you figured out the issue, so we mark as resolved now.. this community is always helpful for learning ..........