root@d1:~# grep nameservers /etc/network/interfaces
#       dns-nameservers 87.117.198.200 87.117.237.100 87.117.196.200

root@d1:~# apt-cache policy resolvconf|grep -i insta
  Installed: 1.63ubuntu16

root@d1:~# cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN