OpenStack virtual machines are called instances because they are instances of an image.
Instances are created from chosen resources, image and size.
When the instance is launched, the size of the instance is resized according to what it actually takes.
Creation of an instance by providing the needed resources.
$ openstack server create \ --image <IMAGE> --flavor <FLAVOR> --network <NETWORK> --security-group <SECURITY_GROUP> --key-name <RSA_KEY> \ <NAME_OF_INSTANCE>
Add the option
--user-data <configuration-file> to customize the creation with a configuration file.
Associate a floating IP with an instance to make it visible and accessible.
$ openstack server add floating ip <INSTANCE_NAME> <FLOATING_IP>
Remote access to instance via SSH.
$ ssh <user-name>@<floating-ip>