I have a device (a single-port terminal server that I use to emulate a serial port) that is accessible via two paths: a microwave T-1 (which connects the device to the internal network at my job) and a public Internet connection via the power company at the remote site. The T-1 goes down from time to time due to atmospheric conditions and whatnot, but the public Internet connection is also not 100% reliable.
I would like to set up a single IP address that would automatically send packets via the best path - either the T-1 or the public Internet connection. Is it possible to do this with a Linux box? I don't have the budget for a dedicated router.