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How can I disable ports so they cant become trunks and send out DTP packet?


Who could verify for me if I am correct. I been looking through cco and cannot confirm this.

My question is how do I disable user ports on CatOS (5k or 6k) from becoming trunking eligible?

If I turn trunking off "set trunk 5/24 off" still sends out DTP packets - correct?

So do you need to "set trunk 5/24 dot1q nonegotiate" which is the only command I found to disable a port from sending out DTP packets - BUT "nonegotiate" will form a trunk if the other end requests it without DTP!

What is the proper way of doing this?

Thank you in advance.....



Re: How can I disable ports so they cant become trunks and send

When set to off/on/auto/desirable, the switch sends frames every 30 seconds to ensure the other end synchs to the current local config. Only nonegotiate doesn't send frames. When configured to off, the interface locally disables trunking and informs the remote end of the local state. If the local port is set to off and it receives a request from a remote switch to trunk, the local switch refuses the request. Setting the port to off forces the interface to remain off, regardless of the state of the remote switch.

So, to answer your question, set the port to off, and it won't be eligible to trunk (it sends DTP packets informing the other end of this and refuses requests to trunk).

Hope it helps.


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