[ovs-discuss] Error: RTNETLINK answers: File exists. MAC duplicate

[Ben Pfaff]

On Tue, Oct 23, 2012 at 10:37:04PM +0400, Denis Iskandarov wrote:
> But i'm interested  in next error/information while restarting network service
> >
> > # service network restart
> > Shutting down interface br0:                               [  OK  ]
> > Shutting down interface eth0:                              [  OK  ]
> > Shutting down loopback interface:                          [  OK  ]
> > Bringing up loopback interface:                            [  OK  ]
> > Bringing up interface br0:                                 [  OK  ]
> > Bringing up interface eth0:  RTNETLINK answers: File exists [  OK  ]
> 
> 
> so as i've unterstood it happens  coz system found two devices with
> same macc address?

I think you will have to find what particular command causes that
message to be printed.  Perhaps there is some more information in the
system log.

(I am not sure that your suggested reason makes sense.)

> As usual bridge taking mac of mathematically smallest? MAC between bridge ports.
> But if it is usual error i will see forever with openvswitch?
> I don't see such for example in Mikrotik products. Or only once before
> i've tried simple linux bridge and it had not such "errors" as well.

I don't understand the paragraph above.

> I'll dare to ask several other simple questions on which i didn't find
> normal answer on google.
> 1.  HOTPLUG=no - what does it do?

I don't know the answer to this one.

> 2. ovs-vsctl - if it can create real system bridge (with system
> scripts, which i can edit, put ip/options)? as i understood from it
> creates only fake/virtual bridges

The bridges that ovs-vsctl creates are as real as any others.  I'm not
sure what you mean by "it creates only fake/virtual bridges".

> 3. i've configured full replacement of bridge with ovs ob system
> (inserted module ... blah blah blah)
> If next output of "brctl show" is normal:

I guess you are talking about bridge compatibility?  I don't recommend
using that feature.  It only works properly with some versions of
brctl and we may have to remove it anyhow in the next release.