[c-nsp] Same MAC addresses from two ports on different VLAN

[Jay Nakamura]

On Sun, Mar 14, 2010 at 8:51 AM, Phil Mayers <p.mayers at imperial.ac.uk> wrote:
> On 03/12/2010 07:21 PM, Jay Nakamura wrote:
>>
>> We have an Extreme Summit switch where I found that if you have two
>> separate ports on different VLANs, and the same MAC address enters the
>> switch on those two completely different VLANs, the switch will start
>> having problems forwarding traffic.  (Or only use the first entry in
>> the FDB, I am not sure what it actually does other than half of the
>> traffic drops.)  Extreme support has confirmed that this is by design.
>
> Which model? We've run several.

Summit X350
XOS 12.0.4.5

Yes, XOS is a little old.  But I don't want to go through maintenance
and upgrade if it won't fix the problem.


> The only time I've ever seen this is when netlogin is enabled; you can't
> have a mac which is inserted into the FDB via netlogin on two ports.
>
> It certainly doesn't happen with "ordinary" configs.

Yet the extreme support people are saying that this is how it is.