MAC flaps on ME3800x

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Mar 16th, 2012
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I'm new to Metro series switches. We basically needed the fiber capacity and bought some of the ME3800X switches to act as distribution switches. We have daisy chains of IE-3000 switches connecting to each of these. There are 3 VLANs per daisy-chain of IE-3000s; management, data, and video. The video vlan serves encoders that multicast video out. We have noticed there are MAC flaps on the Video VLANs everywhere we are doing this. The MAC flaps do not register on the ME3800s, but rather on all of the daisy-chained IE-3000s. There is no loop, so we feel the 3800s are not handling the multicast traffic correctly. Does anyone have any experience with this?

Thank you,


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Overall Rating: 5 (3 ratings)
rsimoni Wed, 03/28/2012 - 12:49
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Hi James,

can you add a basic diagram showing how the switches are connected and pointing out which MAC address is actually flapping (clarifying where the flow is coming from/going to), and which ports see tht MAC address flapping?


satcomjimmy Wed, 03/28/2012 - 12:54
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Sorry, I forgot about posting this. We found that bug ID CSCtq98204 was responsible for the errors we were seeing. I updated code on the ME3800s and it stopped the MAC flaps. Thanks for responding.

rsimoni Thu, 03/29/2012 - 05:16
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good news! Indeed that bug fixed an issue for which mcast traffic was wrongly flooded also to the interface it was received from, causing the flapping.



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