1.How to use config-drive to add another cdrom with my image file? most of the cases people create images on their desktop with VMware player or Virtual box then they will upload that image to openstack because that is more easy and fast way. if you still want to create image on openstack you need to upload the both iso to cinder and attached both volumes before launching instance so it will get detected and start the installation.

2.How to write that script if my image does not have the cloud-init? use following link http://docs.openstack.org/image-guide/content/centos-image.html (http://docs.openstack.org/image-guide...) search for Write a script to fetch the public key (if no cloud-init)