Configure persistent static routes
FreeBSD
Add to /etc/rc.conf:
static_routes="01" route_01="-net 10.0.1.0 -netmask 255.255.255.0 192.168.1.1"
Debian
Add to /etc/network/interfaces to the iface eth0 inet static section:
up route add 10.0.1.0 netmask 255.255.255.0 gw 192.168.1.1 down route del 10.0.1.0 netmask 255.255.255.0 gw 192.168.1.1
Windows
route -p add 10.0.1.0 mask 255.255.255.0 192.168.1.1