hung up troubleshooting packet discards

Posted by Chris Satola on Server Fault See other posts from Server Fault or by Chris Satola
Published on 2012-04-05T16:03:17Z Indexed on 2012/04/05 17:34 UTC
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cisco

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packetloss

I realize my question is generic, but hopefully someone may have some guidance for me. My network consists of Cisco switches. I am seeing a significant amount (upwards of millions of packets per day) transmit drops between two switches. One being a 3750 and the other a 3560. The peak throughput of this link is only upper 400Mbps, so it shouldn't be a bandwidth issue.

At this point, I am sort of clueless where to look or what tools I can use to determine what packets are dropping and why. I can setup a SPAN port on that link and wireshark it, but I don't know if that could tell me anything. Does anyone have any suggestions? Thanks in advance.

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