[c-nsp] Problem VLAN Flapping between trunk port

[Md. Jahangir Hossain]

Thanks peter and jurgen sharing valued information .

i am also trying to find-out this host.







--- On Wed, 6/1/11, Jurgen Marenda <jm at ilk.net> wrote:

From: Jurgen Marenda <jm at ilk.net>
Subject: RE: [c-nsp] Problem VLAN Flapping between trunk port
To: "'Peter Rathlev'" <peter at rathlev.dk>, "'Md. Jahangir Hossain'" <jrjahangir at yahoo.com>
Cc: cisco-nsp at puck.nether.net
Date: Wednesday, June 1, 2011, 12:10 AM


Also make sure your virtual mashines 
do not have the same MAC Adresses.

Juergen.

> On Tue, 2011-05-31 at 22:11 -0700, Md. Jahangir Hossain wrote:
> ...
> > *Mar  1 12:43:54: %SW_MATM-4-MACFLAP_NOTIF: Host 0018.d17b.96d7 in
> > vlan 104 is flapping between port Gi1/0/28 and port Gi1/0/27
> 
> What's behind these ports?
> 
> The switch is complaining that the MAC address keeps moving. 
> It could be
> a loop, but most often (in my experience) it's "misconfigured" hosts,
> e.g. a host with dual NICs that's using some kind of load-sharing
> between ports. I also seem to remember seeing it when IP phones roam
> between wireless access points.
> 
> >From the port configuration it must be something you trust 
> not to bridge
> itself. A VMware server maybe?