I am facing network break problem in my network. I have a layer three switch on which static routes are defined.
and proxy server cyberoam is connected with cisco 4000 series switch. when i telnet our centrel switch cisco 4006
i received messages like this
n port 1/1 and port 2/12 2010 Apr 20 11:33:54 %SYS-4-P2_WARN: 1/Host 00:0d:54:81:f4:c0 is flapping betwee n port 2/12 and port 1/1 2010 Apr 20 11:34:16 %SYS-4-P2_WARN: 1/Host 00:0d:54:81:f4:c0 is flapping betwee n port 2/12 and port 1/1 2010 Apr 20 11:36:17 %SYS-4-P2_WARN: 1/Host 00:0d:54:81:f4:c0 is flapping betwee n port 2/12 and port 1/1 2010 Apr 20 11:36:26 %SYS-4-P2_WARN: 1/Host 00:0d:54:81:f4:c0 is flapping betwee n port 2/12 and port 1/1
where as this MAC address is our layer three switch mac address where routes are defined.
when this message comes our network discoonected for a moment.
You have a loop in your network that is being partially blocked by BPDUGuard. BPDUGuard may be detecting the issue and disabling the port but not before the mac address is learned on the port. Once the port learns the mac address is will propagate through you network on all trunk ports back the your core switch. You will usually see this error for about 5 mintues until the mac address ages out. This can be caused by a user connecting the computer port of a Cisco IP Phone to an available wall jack or by a damaged cable receiving cross talk. If those two ports are both trunk, you need to trace the issue back to the access layer switch the issue is occuring. I have experienced this issue with the mac address of my file server all the sudden appearing on the other side of my campus.
Hi everyone, I would like to thank you in advance for any help you can provide a newcomer like myself!
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