On Wed, Sep 02, 2009 at 08:48:02AM -0400, Gabriel Cane wrote:
> Hello, I need to use two network interfaces in the same logical network. For example, configuring 192.168.0.1/24 and 
192.168.0.2/24 Ip address to each interface.
> 
> But, using netstat -r, I can see that, only exists one route for the network 192.168.0.0/24, and using the first 
interface.
> 
> I tried to add a new route for the same network that uses the second interface, but as result I've obtained an error 
like "file exists".
> 
> The reason of such configuration, is to have redundancy of NIC's in my clients. But, the only way to obtain it, is 
dinamicaly configuring the NIC's when a fail is detected.
> 
> Is possible to get a configuration to reach my objective of redundancy?. Two Nics with two IP addresses in the same 
network, an so, two posible routes to my network. And when a NIC fail, the other NIC start to work, due the existent 
route in the routing table.
> 
> Thanks in advance

This isn't currently possible without some manual intervention
as you've discovered.  What you really need is 'agr' but it's
not currently supported:

http://netbsd.gw.com/cgi-bin/man-cgi?agr++NetBSD-current

-seanb