Bridging problems on IP address conflict

[Oliver Fromme]

Eduardo Meyer wrote:
 > Peter Jeremy wrote:
 > > Eduardo Meyer wrote:
 > > > bridge0: flags=8043<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
 > > >       ether ac:de:48:df:0d:8c
 > > >       priority 32768 hellotime 2 fwddelay 15 maxage 20
 > > >       member: fxp0 flags=3<LEARNING,DISCOVER>
 > > >       member: em0 flags=3<LEARNING,DISCOVER>
 > > > 
 > > > bridge1: flags=8043<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
 > > >       ether ac:de:48:fe:cd:41
 > > >       priority 32768 hellotime 2 fwddelay 15 maxage 20
 > > >       member: xl1 flags=3<LEARNING,DISCOVER>
 > > >       member: xl0 flags=3<LEARNING,DISCOVER>
 > > > 
 > > > And my system constantly reports:
 > > > 
 > > > arp: 00:13:20:1c:33:22 is using my IP address XX.YY.ZZ.KK!
 > > > 
 > > > several (thoundsands of) times. In fact this ARP is my own fxp0
 > > > interface, and this is the only interface that has this IP. What
 > > > should I do? Ass IP on the bridge0 interface instead of the fxp0
 > > > bridge member? Or anything else?
 > > [...]
 > > This may be indicative of a loop in your switch network - is there any
 > > way that packets leaving fxp0 can re-appear on em0, xl0 or xl1?
 > 
 > 5.5-STABLE system. The topology:
 > 
 > - em0 and xl0 crossover (straight from router) to freebsd bridge
 > - fxp0 and xl1 on a common switch (maybe causing a loop?)

Yes, that's a loop.  Packets leaving fxp0 can be sent back
by the switch to your xl1.  You should fix your topology.

Best regards
   Oliver

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Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
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