For fresh installations, you may choose any boot username that you want. However, if you are migrating from an existing repository, it is ideal to use the same boot username as the one used in the repository being migrated. Otherwise, before exporting the repository to the shared location, use Repository Manager to add the new user to the existing repository as a system user.
During the migration process, the installer uses the same boot user as the one set up during the original installation. For cross-platform migrations, such as upgrading to version 18.0, it is recommended to define a boot username that matches the one from the previous installation.
The boot user is the account used to set up the initial installation and is also used in
commands like ./mtb_admin -user <bootuser> -password
<bootuserpassword> during the migration process.