Situation is manifest when these two commands are run during samba 4 provisioning
samba-tool domain passwordsettings set --complexity=off --min-pwd-length=6
samba-tool domain provision --realm=******.example.com --domain=****** --adminpass=111111 --server-role=dc
The expected result is a successful provisioning, however the outcome is either of password to short or not complex enough.
The provision wipes any existing settings, including password complexity settings.
To set a weak admin password, do so after you provision.