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I have multiple servers with 2 LAN cards each.

I want to use their second LAN cards to connect them to each other using a network switch.

My question is - How do I 'join' the networks together on the OS level, using the private network ip range for the second connection.

Basically I want every server to connect to the Internet normally, except when using the 10.x.x.x ip range, in which case the local connection is to be used.

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Have you found that they don't do this normally? – Ignacio Vazquez-Abrams Mar 28 '12 at 18:39
up vote 5 down vote accepted

The server's routing table will naturally prefer directly connected routes.

Say that eth0 has IP address, and eth1 has, with default gateway only set on eth0. Then eth1 will be used for packets with a destination of, and eth0 for everything else but localhost.

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