We have a Cisco 3750 switch stack and I have a few devices that will randomly drop off the network. The devices are 3 APC UPS management cards and 1 Cisco Wireless 4402 Controller. This problem has just recently developed. I have checked to make sure we don't have any physical loops in the network. I would not swear that we don't have duplicate IP addresses but if we do, I can't find them.
Any ideas on how to trouble-shoot this problem? Do you know of a MAC address scanner that can show me devices that have devices that have duplicate IP addresses?
Thanks