Firesox wrote: > > Well, the thing is the MAC addrss appears to be moving around > thruout the > network. > One time I see the mac stored in one switch, then onto another > switch the > next. > Another time, the MAC address disappears from the network all > together. > Whatever this mac is, it's causing the duplicate IP on the > network and > bringing the applications down.
Does this IP address belong to one of the servers? Is that why it brings down the applications?? Is there some sort of routing/addressing problem caused by a misconfigured attempt at load balancing so that sometimes the servers see each other directly and sometimes the packets flow through a router (picking up the router's MAC address?) What is this MAC address? Perhaps the vendor code will help you understand what's happening, as others mentioned. If it's a router manufacturer, that could mean something like what I described. I suspect there's more to this story and that some advanced, convoluted features related to load balancing, clustering, redundancy, VLANs, etc. have done what advanced, convoluted features tend to do: get mucked up. :-) Please tell us more if you can. Thanks. Priscilla Oppenheimer > > > ""Pat Donlon"" wrote in message > news:[EMAIL PROTECTED] > > Firesox wrote: > > > I have a bunch of 3500XL switches thruout my customer's lan. > > > They are having a problem with unknown mac keep appearing > and > disappearing > > > from the network. > > > > > > I can trace the mac-address of the unknown station by "show > mac" from > the > > > swtich CLI. > > > What's strange is that it appears at one switch, but a > minute later it > > > appears in the different switch. > > > > > > what's even more strange is that all NT/2000 servers log > shows there is > an > > > IP conflict with this mac address. > > > Of course, the servers IP function stops due to this > duplicate IP, but > > comes > > > back in a few minutes. > > > All the servers report the duplicate IP comes from the same > mac address. > > > > > > Has anyone seen this problem? > > > > > > Thanks > > > **Please support GroupStudy by purchasing from the > GroupStudy Store: > > > http://shop.groupstudy.com > > > FAQ, list archives, and subscription info: > > http://www.groupstudy.com/list/cisco.html > > > > > I know that the NT team where I work had a batch of new HP > netservers > > delivered last year with the built in NICs with all the same > mac > > addresses. They had to perform a bios upgrade I think to fix > the > > problem. You should probably try to find out where what > port(s) the > > duplicate mac and IP appear. > > > > Cheers > > > > Pat > > **Please support GroupStudy by purchasing from the GroupStudy > Store: > > http://shop.groupstudy.com > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=73929&t=73868 -------------------------------------------------- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
