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Switch Port flapping


I'm new in forum. I hope i can get some help here, and as i can see I can really start to help in some topics Happy

So, here's my question.

I have a simple switch of 24 ports from ZTE and I have another equipment contected to it in one port.

The port is UP, but i can't ping the equipment. After 1minute (sometimes more, sometimes less) when port learns the other equipment's MAC ADDRESS it goes down.

I already tested. The port is up while i'm checking MAC table and there's no mac in port. When finally port learns the MAC i will check port state again and it is down. Some seconds later port is UP again and everything starts again.

Anyone have a idea what's can be the problem?

i already check negotion parameters and mac learning. It's everyting OK.

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Sorry but PING is not a sure thing.

In reply to: Switch Port flapping

I have equipment that never replies to PING. However the story sounds like someone made their own cables or if they used punchdowns got the pairs wrong.

The MAC table is good information, PING is not.

So given the light story, I'll wait for more.

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More info

In reply to: Sorry but PING is not a sure thing.


Thank you for the answer.

Ping is. Because connected to other switchs from other vendor the ping is OK.

The cable is not a problem also. It is a large scale network and I have this situation replicated in other locations. None of them works. Happy.

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Large scale means you have a big hammer.

In reply to: More info

If the other vendor product works, use them. Why use defective gear?

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It's a very strange sittuation

In reply to: Large scale means you have a big hammer.


It is a very complex situation. I have to change the equipments for other reasons. I really have to.

Another thing i have tried is to force port to a permanent MAC ADDRESS. Nothing happens. Exactly the same.


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Given the facts.

In reply to: It's a very strange sittuation

It looks simple from here. One device works the other is defective.

Of course you could have the old boss issue. That is, the boss wants to use the new cheap defective box. I know of no cure for that issue.

Back to the maker and ask if they can fix it.

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