i have a twrk60n512 where I have set up two network interfaces, one wired ethernet and one GPRS (PPP over serial, using ittyd:), with the intention of having two redundant paths to the internet. The operation would then be something like 1. create and bind a tcp socket to the primary interface (wired ethernet) and try to connect. If connection is not complete in say 10 seconds, then close the socket and 2. create and bind another tcp socket to the secondary interface (GPRS) and try to connect.
Now I realize there might be some issues here. First, i'm not sure if the socket bind function can be used to determine which interface will be used for an outgoing connection. Second, there seems to be no straight-forward way of setting the socket connect timeout to anything less than 3 minutes. Third, the two interfaces are bound through DHCP and IPCP respectively, so I guess there would be a need for a separate default gateway for each interface, but this is not supported by RTCS?
Any suggestions on how to solve these issues?