Hi Kumar, I think you're at Step5 where it asks you to create admin user Running Setup
If you're using Active Directory enter username=domain\username
Step 5: Create a Tableau Server administrator user
The final step is to add an administrator user for Tableau Server. After the configuration is all set, Tableau launches your browser and presents a page where you set the administrator user for Tableau Server.
The Tableau Server administrator is a user within Tableau Server who can manage all aspects of Tableau, including managing sites, users, groups, and projects, plus change server configuration settings.
- If you are using Active Directory for authentication, then the account that you specify here must be a user in the directory.
- On the other hand, if you are running Tableau Server with local authentication, the username and password that you specify here will be used to create the administrative account. Enter a strong password for this account.
Use this account to access the Tableau Server admin web pages. See Sign in to Tableau Server Admin Pages.
Keep the user name and password for the administrator in a secure place! First, the administrator user in Tableau Server has complete control over the server, so make sure that the credentials are kept secret. Second, you need these credentials to create additional users on the server, and this user is your ultimate entry point into the server if something happens.
You can add or change server admin accounts anytime. We'll cover that later in the Creating Userschapter.
the Tableau Services Manager (TSM) user/password you are being prompted for need to be someone with local administrative access to the computer where Tableau Server is installed. It can be the person who installed Tableau, or another person with administrative access on the computer. It does not need to be a user with an account on Tableau Server.
This link might help explain it: Sign in to Tableau Services Manager Web UI
Also, note that I'm assuming you're on Windows. The details are similar but slightly different for Linux.