hmmm sorry since this is a old thread but i'd like to point out that there is a --savemasterpassword flag for create-domain,create-node-agent,and change-master-password commands which will create an encrypted master-password file. this will stop prompting for master password. not to sure if this exist for the admin password...but one less unencrypted password showing in some password-file.
hope this helps future ppl who is searching for this =D
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