Comment 3 for bug 1621501

host:
 cat /etc/*release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=16.04
DISTRIB_CODENAME=xenial
DISTRIB_DESCRIPTION="Ubuntu 16.04.1 LTS"
NAME="Ubuntu"
VERSION="16.04.1 LTS (Xenial Xerus)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 16.04.1 LTS"
VERSION_ID="16.04"
HOME_URL="http://www.ubuntu.com/"
SUPPORT_URL="http://help.ubuntu.com/"
BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/"
UBUNTU_CODENAME=xenial

DIB:
declare -x DIB_CLOUD_INIT_DATASOURCES="NoCloud, OpenStack"
declare -x DIB_DEBUG_TRACE="1"
...
declare -x DIB_RELEASE="xenial"
declare -x DIB_REPOREF_ironic_agent="stable/mitaka"'

+ disk-image-create --no-tmpfs ubuntu labomatic-hostname labomatic-proxy dynamic-login baremetal labomatic-sshd-pwauth labomatic-nis labomatic-sieopenstack-sudoers dhcp-all-interfaces -o /labomatic/images/ubuntu16_minimal

non of the elements except for dhcp-all-interfaces touch any of the network interfaces configuration