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Re: [Openvpn-users] Three-way bridge setup


On Mon, Jun 04, 2007 at 11:25:37AM +0200, Stefan Bethke wrote:

> If I enable Spanning Tree Protocol on the bridges, this problem is  
> avoided, but all traffic between A and C will go via B (if B is  
> established as the STP root node), even though there is a direct link  
> between A and C.

Well, when using bridging in this kind of a redundant setup you *must*
enable STP in order to avoid loops because the ethernet protocol has no
loop detection like a TTL in IP protocol. This would be exactly the same
when you replace the OpenVPN tunnels by ethernet switches. In this case,
STP provides you with an automatic failover due to a topology change
(eg. in case of a link loss).

> I could change to a routed configuration, but that would make certain  
> applications more cumbersome.  Is anybody running such a configuration?

A routed configuration makes it possible to use all links simulaneously
and dependent of your destination address. Additionally you get rid of
 broadcasts running over the link.

Best regards,


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