octavia/elements/apt-mirror/README.rst

This element enables the use of a mirror for updating Ubuntu cloud images. Using a local mirror increases the speed of building the image.

Note: This element is deprectated in favor of the diskimage-builder methods for setting a mirror. See http://docs.openstack.org/developer/diskimage-builder/elements/ubuntu/README.html and http://docs.openstack.org/developer/diskimage-builder/elements/apt-sources/README.html for more information.

The Ubuntu mirror URL is specified by setting the 'UBUNTU_MIRROR' environment variable.

$ export UBUNTU_MIRROR=http://<local mirror hostname>/<path to mirror>