MAC Flapping

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I have twenty-five devices of eXtreme switch type Summit X450-24X DC with software version 15.3.1.4 patch1-38 , I'm facing problem with Flapping MAC.. my question, how do I Know Since when has been getting this Flapping?
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MUNIR ENG

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Posted 3 years ago

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Henrique, Employee

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Hi Munir,

You can add a log entry to track the MAC-Moves and be notified as soon as the flapping starts.

Since this can add lot of log entries you can enable a syslog server or even increase the switch log buffer from 1000 to 20000.

If the flapping already started and if you didn't have those logs entries added, I don't believe you will be able to find the exact date/time.
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Brandon Clay, Escalation Support Engineer

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In addition to what Henrique suggested, if you are seeing MACs flapping, you may have a loop. I would suggest running ELRP on the problematic VLAN.

-Brandon
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Drew C., Community Manager

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You could also have duplicate IP addresses somewhere on the network.
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MUNIR ENG

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thank for your replayو How to reset the counter of Link UP/ Link Down  to zero?
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Henrique, Employee

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Hi Munir, you can use the command clear counters port <port_number>
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MUNIR ENG

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thank you