----- "Juan Araya Bravo" <juan.araya@xxxxxxxxx> wrote: > Hi, this is my first message to the list and first of all i apologise > for my very bad English. > > The thing is i have one machine with three NIC cards acting as a > gateway. One of the NIC (eth0) is connected to LAN and the others are > connected to two different ISP (eth1 = ISP A and eth2= ISP B). > > I was looking for a rule that let me determine specifically which IP > can use the ISP A and let all the others to use the ISP B connection. > > Also i need that when one of the connections fails all the traffic > will be directed by the one which works. > > Please help me with a link or something i can read to learn how to do > it. What you're essentially describing is called Source Policy-Based Routing (PBR). Here is a good place to start reading, http://lartc.org/howto/lartc.rpdb.html http://lartc.org/howto/lartc.rpdb.multiple-links.html Those pages will help you get the big picture, and the "ip rule" section of "man ip" can help fill in a lot of the details. The 'gwping' script mentioned elsewhere in this thread is a good example of how to continuously monitor the responsiveness of the two uplinks and stop routing traffic out a failed link. That's where the fail-safe part comes in. However, that script seems to use stateless, per-packet load-balancing which is going to come with its own set of problems. When you understand both PBR and the gwping script, you can probably put together a script using ping tests and failover like gwping with a true source PBR implementation. -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
