Ubuntu: DNS configuration + multiple IP addresses on one interface

/etc/network/interfaces:

auto eth0
 iface eth0 inet static
 address 192.168.47.15
 netmask 255.255.255.0
 gateway 192.168.47.1
 dns-nameservers 8.8.8.8

auto eth0:1
 iface eth0:1 inet static
 address 192.168.47.14
 netmask 255.255.255.0

auto eth0:2
 iface eth0:2 inet static
 address 192.168.47.16
 netmask 255.255.255.0