Emmanuel Noobadmin wrote: > I've got a server that initially was connected to a static WAN > connection via eth0. Now I've added a second NIC eth1 connected to a > local network switch with the intention of using it as a backup remote > access connection via a dynamic ADSL connection. > > The problem now is getting the IP address of the dynamic ADSL connection. > > I've written a script that updates another server with the current IP > address in order to ssh in which was used on my own home server also > running Centos 5. But in the case of two NICs, I cannot find a way to > make the outbound traffic of the script use eth1 instead of the > default gateway on eth0. > > There are instructions on using iproute to ensure that a connection > coming in from eth1 will work properly. But this only appears to work > for when the connection is initiated externally through eth1. > > The only way I found that might work is adding a static route, but > then this assumes that I'll always be connecting from the same > external IP. > > Does anybody know if what I'm trying to achieve is possible? You need policy routing. And it is possible. My suggestion is to use shorewall (http://www.shorewall.net/), there are rpm's for download, and use it's "Mult-ISP" feature (http://www.shorewall.net/MultiISP.html). Webmin can be of some help with setting it, it even supports manual edit of config files (you will need it for part of the setup.) Ljubomir