I believe ipchains can provide the source address routing you are looking for.
http://netfilter.samba.org/ipchains/HOWTO.html Matthew ----- Original Message ----- From: "Dan Sugalski" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, November 28, 2001 9:49 PM Subject: [Boston.pm] [OT]Multihoming Linux? > Okay, so with @Home potentially going toes-up soon, I've finally gotten the > push I need to get my home box properly multihomed, and I'm having a heck > of a time. > > The short bit is I've a Linux 2.2.19 system with a pair of NICs in it. > eth0's hooked to a cablemodem with an IP address of 24.8.96.48, eth1 to a > DSL line with an IP address of 63.120.19.219. (tuatha.sidhe.org and > redcap.sidhe.org for the curious) Both NICs are up and working, and > accessible from their appropriate LANs. (Yeah, I've two separate network > segments in my apartment. The Geek Force is palpable from miles away... :) > > What I want is for packets coming from 24.8.96.48 to go out eth0, and > packets coming from 63.120.19.219 to go out eth1. Nothing fancy, I don't > want load balancing or failover or anything of the sort. (Both IPs are > listed as MX entries for sidhe.org, and both are listed as > nameservers--basically I want my names to always resolve, my mail to get > delivered, and to be able to ssh into the functioning interface if one goes > down, and the rest can be hand-patched) > > Unfortunately, this has turned out to be non-trivial. > > The standard default route, courtesy of /sbin/route, sends everything out > 24.8.96.48 and, while @Home is whacky in so many profound ways, the cable > modem *does* block packets that don't either originate from or are destined > for one of its IP addresses. Which is good from a number of perspectives, > just not this one. /sbin/route, unfortunately, only puts in routes based on > a packet's destination IP address not its source, so it looks like it just > won't do. > > iproute2, OTOH, looks like it does have the power to set up source-based > routes, but it beats the heck out of me how to set it up so that it > actually works. All the examples seem to assume that you're routing packets > from other machines not yourself, and my attempts to get it functioning > haven't done much besides black-hole everything. (Which is hardly useful) > > So... Help? > > Dan > > --------------------------------------"it's like this"------------------- > Dan Sugalski even samurai > [EMAIL PROTECTED] have teddy bears and even > teddy bears get drunk > >
