virt-install-cloud/user-data

#cloud-config
users:
 - name: testuser
   lock-passwd: false
   passwd: hashed-passwd-here
   ssh_authorized_keys:
    - ssh-key-here
   sudo: ['ALL=(ALL) NOPASSWD:ALL']
   groups: sudo
   shell: /bin/bash

ssh_pwauth: True
package_upgrade: true

apt_upgrade: false

manage_etc_hosts: true

fqdn: %FQDN%

timezone: US/Mountain

manage_resolv_conf: true
resolv_conf:
  nameservers: ['%NAMESERVER1%', '%NAMESERVER2%']
  searchdomains:
    - %DOMAIN%
  domain: %DOMAIN%

#datasource_list:
# - ConfigDrive

packages:
  - openssh-server
  - nano

runcmd:
  - [ touch, /etc/cloud/cloud-init.disabled ]
bootcmd:
  - [ mv, -f, /etc/network/interfaces.d/50-cloud-init.cfg, /etc/network/interfaces ]