rpi_detector
	- dicovery module, use any way to detect ip by partial mac address 
	- use the ip to create ansible inventory
    optional
    	- test for standard login methods # integrated in rpi_ssh
    	    - ssh with password
    	    - ssh with key
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rpi_inventory
	- use detector to get _list_ of Rpis
	- rpi_ssh
	- generate ansible inventory based on a template
	    - use templates for role definition
	    - 
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rpi_ssh
	- test for default ssh login methods
	   - ssh with password
	       if true continue to switch to key, else ssh with key
    	   - ssh with key
    	       if policy mandates switch to key, else exit
    	- switch to key
    	    - use pre-defined root key
    	    - generate root key
    	# if used for key deployment use this strategy
	- generate keys based on the _list_ for root
	- generate keys for defined users
	- generate authorised_keys files 
	- copy to defined folders
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rpi_create # will be used to deploy OS on raspberry pi with netinstaller
	- use template to generate
	    - installer-config.txt
	    - post-install.txt
	- copy needed files (authorized-keys, hosts, rules etc.)
	- update/change boot-loader
	- if local repository is used verify accessibility, update and verify needed packages
	- restart all affected machines to start creation process
	    - use base image  if available
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rpi_provission
    if used as stand alone app:
        - rpi_detector
        - rpi_inventory
    else
        - run update, upgrade playbook
        - run role provision playbooks

rpi_deploy
    - playbook for environment verification
    - playbook for deployment
    - playbook for deployment verification

rpi_monitor
    - monitor demon for controlling cluster status
    - failure detection and re-install