You should add
devices variable to the
host_vars of your first node.
If you have an inventory directory you can add
host_vars directory in your inventory directory and add a file with your hostname in your hosts. For example if you have node1 in your
hosts.yaml you should create a file named
host_vars directory and add
devices variable in it so this variable is just used for this host.
You can find more info about
host_vars here: https://docs.ansible.com/ansible/latest/user_guide/intro_inventory.html#organizing-host-and-group-variables
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