Thanks to
phoenix help I was able to setup multiple default routes, or a default route per network/interface to be precise, in Debian/Linux it is as simple as that:
/etc/network/interfaces
Code:
iface eth0 inet static
address 10.0.0.1
netmask 255.255.255.0
gateway 10.0.0.254
iface eth1 inet static
address 20.0.0.1
netmask 255.255.255.0
gateway 20.0.0.254
That would be example topology (but more then 2 interfaces is also possible).
Code:
NETWORK0 NETWORK1
\ /
\ /
\ /
\ /
\ /
ROUTER0 ROUTER1
10.0.0.254 20.0.0.254
\ /
+------\----------------/------+
| \ / |
| em0 em1 |
| 10.0.0.1 20.0.0.1 |
| |
| FREEBSD BOX |
| |
+------------------------------+
Now, You can not use the 'casual'
defaultrouter="X" cause it will be only for one network.
We will have to use
setfib(1) to create two (or more) separete routing tables per network/interface.
Add these lines to
/boot/loader.conf file:
Code:
ipfw_load="YES"
net.fibs=16
It will unfortunately require kernel recompile, but its not as that hard:
Code:
# cd /usr/src/sys/$( uname -m )/conf
# cp GENERIC /root/ROUTES
# ln -s /root/ROUTES
# echo "options ROUTETABLES=16" >> ROUTES
# cd /usr/src
# make NO_MODULES=1 kernel KERNCONF=ROUTES KODIR=/boot/routes
# mv /boot/routes/kernel /boot/kernel/kernel
# reboot
We can of course set 2 instead of 16, but You will at least have to recompile Your kernel again and reboot which is not very handy ...
Nest set your networks/interfaces as usual in
/etc/rc.conf file:
Code:
ifconfig_em0="inet 10.0.0.1/24"
ifconfig_em1="inet 20.0.0.1/24"
# check /etc/rc.local for default routes
All the rest configuration resides in
/etc/rc.local file:
Code:
# define default routes
setfib 0 route delete default
setfib 0 route add default 10.0.0.254
setfib 1 route delete default
setfib 1 route add default 20.0.0.254
# assing route tables to interfaces
ipfw -f flush
ipfw add allow ip from any to any via lo0
ipfw add setfib 1 ip from any to any via em0
ipfw add setfib 0 ip from any to any via em1
ipfw add allow ip from any to any
These would be handy for restarting:
Code:
# /etc/rc.d/netif restart
# /etc/rc.d/local restart
... and thats all folks.