Backgroup- we recently found some alarm info in Hp Openview that reported some server down and up(flapping)in a short time.These are in vlan11 in cisco 4507R,also these server has second net adapter to connect another vlan 9 in 4507R,We checked 4507 logging no find some down and up info for interface.Check the server status also is ok.My quesion is whether it once really down or not,aside from that, i wonder if just to occur in vlan 11 and other is ok,we current hold that it caused as resault of older IOS(12.1(20)EW2). And no more ideas for that.I was not found more caveats for this ios version.I wanna know whether it could solve via upgrade ios.For some reason,I can't open case via my CCO.Who can give me some ideas.Attachment is result of show tech.
If no logs has been genrated on Switch and no logs have been genrated on Server , then i guess problem might be in HP open view.
Yes log will be genrated for port flapping. Just be sure that you are viewing the log of that time only when its showing on HP open view or if the time difference is there between those two , then you are calculating it right .
Because the equipment was not on my side.I can do test that pull and insert cable to check logging whether it will genrated.I attmped find a offical explanation to prove the port is ok for customer due to i current can't open case from cisco tac.
If it could have been STP issue , then i guess it would have gone into permanent block state , moreover if there was STP issue it must have genrated log on switch .Morelight can be put by by the owner ........
At this point of time you will not able to tell what all ports got flapped.
In Cat4K IOS it be default doesnot generate logs for link flapping, that's why you were not able to see the logs and hence track the ports.
Please enable "logging link event-status " command under the interfaces to send the log to the switch buffer or syslog server. This will help you for sure in the near future if you have that kind of problem.
Now the release notes show me that starting from 12.225SG we have the suport for the above listed command but I am pretty sure that I have even used it on 12.1.20EW. Please check that.
HTH, Please rate if it does.
AFAIK vlan interface generally do not flap till the time all the ports at layer 2 on which vlan is been configured are flapping.
If even one layer 2 port for that vlan is up or if you have a trunk port which carry that vlan is up the vlan logical interface will not flap.
Incase vlan is deleted from vlan database the logica linterface will go down but will not flap.
HTH, if yes please rate the post.