Howdy,
Yes, there is a way to manually (and auto-magically) assign alternate IP ranges to your NIC. Below, I'm assing `10.1.1.34' to `eth0' and it will handle the entire C class: 10.1.1.x:
sh code:
$ ip addr add 10.1.1.34/24 dev eth0
$ ip addr show dev eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc vboxnetflt state UP qlen 1000
link/ether 00:24:8c:7e:eb:e1 brd ff:ff:ff:ff:ff:ff
inet 192.168.25.6/24 brd 192.168.25.255 scope global eth0
inet 10.1.1.34/24 scope global eth0
inet6 fe80::224:8cff:fe7e:ebe1/64 scope link
valid_lft forever preferred_lft forever
$ ip route show
10.1.1.0/24 dev eth0 proto kernel scope link src 10.1.1.34
192.168.25.0/24 dev eth0 proto kernel scope link src 192.168.25.6
169.254.0.0/16 dev eth0 scope link
127.0.0.0/8 dev lo scope link
default via 192.168.25.1 dev eth0
$ ip addr del 10.1.1.34/24 dev eth0
$ ip addr show dev eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc vboxnetflt state UP qlen 1000
link/ether 00:24:8c:7e:eb:e1 brd ff:ff:ff:ff:ff:ff
inet 192.168.25.6/24 brd 192.168.25.255 scope global eth0
inet6 fe80::224:8cff:fe7e:ebe1/64 scope link
valid_lft forever preferred_lft forever
HTH.
Cheers,
-pablo