I've only had this issue twice, but it's enough to concern me. I was doing some maintenance and checking on my Catalyst 4507 when all of a sudden the switch threw a ton of messages at me, and proceeded to reload. The only one that I could see was there is a switch trunking on another VLAN that my 4507 said it had received an invalid MAC Address of 00:00:00:00 and then it reloaded. When it came back up, it said that the port that that switch was connected to was in errdisable. What can I do to investigate further, and has anyone else seen this issue? Please advise!!