From: "Trent W. Buck" <trentbuck@gmail.com>
If you want both links up at once to double your throughput, or for failover (to avoid a SPOF in the NIC), you want what's called "trunking" or "bonding". It's slightly tedious and flaky; mostly I wouldn't bother.
I did this in the past... I just used Google to search for "Linux bonding" to see that not much has changed it seems(?). You find "generic" Linux commands and configuration examples for Red Hat/CentOS and Ubuntu etc. I use it under FreeBSD just now, it's called a "lagg" interface there (link aggregation and link failover interface) but the result is the same. http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-aggregatio... The only "flakiness" I experienced had to do with confused switches. The Ciscos I have at the moment are okay. The handbook above touches the Cisco part too, as well as "how it works" (also useful for penguins). Regards Peter