out of the box master password?

I am looking to try out Payara6(been using Payara5 for a while now)

I have downloaded the Community edition latest version, unzipped it and tried running asadmin start-domain but it is asking me for a master password. I have no clue what this is, tried admin, changeit, default, blank etc

I cannot find a mention to it in the Payara documentation either.

What am i missing here?