Linux – Network balancing/failover on linux

linuxnetworking

I've a CentOS 5.4 server it has 2 nics. Is there any way I can configure this box to use the 2. nic as a failover if the physical connection on the 1. nic fails ?

This is an internal server that has no connectivity to the internet. I can wire the 2 nics to 2 different switches, though all on the same subnet. It should have just 1 IP address.

Can linux now also load share (atleast the outgoing packets) on both these nics ? Any step-by step guide appreciated.

Best Answer

What your talking about is usually referred to as bonding. In alot of cases interfaces are grouped (or bonded) together to increase bandwidth. In your case, the setup will be the same, only when you configure the mode for the bonded interfaces, you tell the system to use one of the two interfaces as a fail-over.

Check out the how to at http://www.howtoforge.com/network_card_bonding_centos. It both explains and walks you though bonding interfaces in CentOS.

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