I am new in networking. Sorry for my ignorance.

I have three switches.

Switch 1 has 4 ports. Two of them connected to switch 2. And the other two ports are connected to switch 3. All these four ports are in the same link aggregation group. (I am using LACP by the way).

The same configuration was made in switch 2 and switch 3. (Switch 2 has 4 ports. Two of them connected to switch 1. And other two port is connected to switch 3. All these four ports in same link aggregation group.)

I am not using spanning tree protocol. Also for link aggregation protocol, I am using src ip to dest mac address configuration.

Each switch is connected to at most three computers.

Does this configuration of switches create loops?

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  • "I am not using spaning tree protocol." You better believe that's a paddlin'. – womble Nov 12 '15 at 20:48
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    What's the point of doing this? If each switch has only four ports then you've used up all of the ports by connecting them all to the other switches and you've left no ports available for connecting hosts or other network devices to. – joeqwerty Nov 12 '15 at 20:48
  • I said it to simplfy the question. But, of course there will be host and other devices. – ysnfrk Nov 12 '15 at 20:53
  • OK, then please edit your question to reflect the actual configuration. Don't post hypothetical or theoretical information. Post real information. – joeqwerty Nov 12 '15 at 21:10
  • The information I seek is whether link aggregation groups prevent loops when we connect same aggregation group to two different switches. And I did not establish the actual configuration. I will be establishing the actual configuration depending on this information. – ysnfrk Nov 12 '15 at 21:21

Yes, unless you use spanning tree (or a vendor specific equivalent like EAPS) to create a loop free network you will have problems, LACP does in no way help you to prevent loops, it was not designed to do so.

You either make one of the paths in the triangle blocking with spanning tree, or perhaps (if your equipment supports this) create a virtual chassis using techniques like TRILL, FabricPath, Qfabric or VCS which allows you to connect all switches loop free.

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