the admin-secret is intended to be used to access the underlying Zookeeper service which serves as the point of communication for all of the juju agents and clients.
admin-secret:
A secret that will be generated for you when config is created.
secret-key:
The AWS secret key to utilize for calls to the AWS APIs.
control-bucket:
Name of a Swift container unique to the environment for metadata and charm storage. Also generated when config is created.
control-bucket:
An S3 bucket unique to the environment, where some runtime metadata and charms are stored.
s3-uri:
The S3 endpoint, or set S3_URL.
combined-key:
The access key for the OpenStack/AWS compatibility layer. In typical configurations this will be a combination of the project name or id and the normal access key. Alternatively set EC2_ACCESS_KEY.
the admin-secret is intended to be used to access the underlying Zookeeper service which serves as the point of communication for all of the juju agents and clients.
Due to this bug, however, it actually isn't used:
https://bugs.launchpad.net/juju/+bug/813773
So, for now you can mostly ignore it, but in the future it will be like the "root" password for your juju environment.
This is what i found i might be wrong if i am sorry
https://juju.ubuntu.com/docs/about.html
admin-secret: A secret that will be generated for you when config is created.
secret-key: The AWS secret key to utilize for calls to the AWS APIs.
control-bucket: Name of a Swift container unique to the environment for metadata and charm storage. Also generated when config is created.
control-bucket: An S3 bucket unique to the environment, where some runtime metadata and charms are stored.
s3-uri: The S3 endpoint, or set S3_URL.
combined-key: The access key for the OpenStack/AWS compatibility layer. In typical configurations this will be a combination of the project name or id and the normal access key. Alternatively set EC2_ACCESS_KEY.