For UNIX systems, you can specify any valid local user account with a password or SSH key. When using a password for that account, however, you would likely specify root or an account with similar privileges for which you want to manage the password. If you want to use a SSH key for that account, you must have a key uploaded to Privileged Access Service. See Adding SSH keys .
If you have added an account with a password, you can also choose to have Privileged Access Service manage the account password. Password management means that Privileged Access Service automatically resets the password after the account and system are added and each time the account is checked in. See Adding accounts for a system for information about configuring password management.