Thanks @Julius Kos for your help!
I'm on a cloud trial instance, thats right. Still no success so far.
I've created a user in Amazon IAM with fully redshift:* permissions. Questions:
• do I need to create an access key (key and secret) and use that as username and password? or
• do I need to create a console login with a password? Is the username then the fully ARN of the user, or only the username?
• are you aware that in Amazon Redshift, there is a whole configuration about "Data-Access" from outside (VPC config, Subnets, ...) - nothing is mentioned in the docs if I need to configure something there
• the docs talk about "Basic authentication is supported. Specify user and password." - Where would I setup Basic Auth in Amazon IAM?
I'm not sure if the documentation is lacking a lot of information or maybe Amazon has built a lot of security features into Redshift which is not covered right now, but I'm pretty sure, its not possible to setup the connection for me right now.