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New Member

Caveat in Cisco IOS switches

Recently we had an experience in Cisco Switches where in we were troubleshooting clustering on Cisco 3550 switches and contacted TAC for help. Without knowing our environment the TAC engineer asked us to change the VTP status from transparent to Server. This had a disastrous effect and brought the connected networks down for several hours. I would like to know what other commands to avoid in IOS switches or could it be some thing what I mentioned above which I am not aware of.

New Member

Re: Caveat in Cisco IOS switches

The list of commands to be avoided if you are unsure of their consequences are too numerous to be listed in this forum. My suggestion would be that no matter who tells you to enter a command or make a change that you are unsure of, make that person explain the consequences of the change. I don't even make changes suggested by my Cisco SE who knows my environment, without grilling him of the consequences of those actions if I'm unsure. They don't mind, and if they do, ask to talk to someone else. If you're not satisfied with the answer, get a second opinion from another engineer. While the TAC is, in my opinion, an excellent organization, they are human and prone to make mistakes. You as the network individual making the changes are ultimately responsible for those changes and the consequences of those changes.

New Member

Re: Caveat in Cisco IOS switches

I am not making comment on TAC and I do know TAC is excellent support from Cisco and I highly commend the amazing documentation and answers for the network problems. Also I am highly appreciative of this forum where I get excellent feedbacks and answers like yours. It is worth while to mention here that from one of the network management forums I got to know what is called community string indexing when we are dealing with VLANS in switches. I am coming from nortel switching environment and I have very little knowledge of Cisco products. You are right about the command structure and one should not administer without the knowledge of it. But mistakes could happen and my question was as how to circumvent those kind of mistakes. Thanks.


Re: Caveat in Cisco IOS switches

The irony here is that Cisco Best Practices Document for Catalyst switches says NOT to use VTP.

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