eth0: 2.2.2.2 ( route like a normal )

eth1: 1.1.1.1 netmask 255.255.255.255 ( OVH )

# make this IP append to table Route1
ip rule add to 1.1.1.1/32 table Route1
ip rule add from 1.1.1.1/32 table Route1

# this IP push directly to eth1
ip route add 10.10.10.10 dev eth1

# and main think, put default route for this table
ip route add default via 10.10.10.10 dev eth1 table Route1