default gateway not set when using bond0 interface

This is my /etc/network/interfaces file: auto bond0 iface bond0 inet manual address 10.66.7.11/24 gateway 10.66.7.1 bond-mode 802.3ad bond-slaves eth2 eth3 bond-miimon 100 bond-downdelay 200 bond-updelay 400 bond-lacp-rate 1 up ifconfig bond0 10.66.7.11/24 up when I bring the bond0 interface up, it works, but the default gateway is not set # route -n Destination Gateway Genmask Flags Metric Ref Use Iface 10.66.7.0 0.0.0.0 255.255.255.0 U 0 0 0 bond0 I have to set the default gateway manually, and then everything works fine: route add default gw 10.66.7.1 bond0 #route -n Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 10.66.7.1 0.0.0.0 UG 0 0 0 bond0 10.66.7.0 0.0.0.0 255.255.255.0 U 0 0 0 bond0 why is my default gateway not set automatically, when I have it defined in the /etc/network/interfaces file ?