CLI Cookbook: Changing the Default admin username
The default domain user created on Delphix Engines is now admin instead of delphix_admin. When engines created before 5.3.1 are upgraded to 5.3.1 or later they will retain their old username 'delphix_admin'. To avoid complications Delphix recommends creating users with an admin role and then Disabling delphix_admin.
To change the default admin username.
ssh into your engine
Go to users and select admin.
Change the name to admin.
Commit the operation.
Example
delphix.engine> user select admin
delphix.engine user 'admin'> update
delphix.engine user 'admin' update *> set name=dlpxadmin
delphix.engine user 'admin' update *> commit
delphix.engine user 'dlpxadmin'>