From RAP click on the eduGAIN logo and select INAF as you Identity Provider.
Remember that IDEM credentials username is name.surname, without the @inaf.it suffix.
IA2 doesn't manage these credentials directly, so if you can't login consider to use following URL for performing password reset: https://www.ced.inaf.it/passwd/index.php.
You have an IA2 account. From RAP click on the IA2 logo for using these credentials. You can consider to join this account with an eduGAIN or social account (see explanation in the home page of this site).
For older account your username in an e-mail address. For newer account your username is name.surname.
If you have lost your password you can receive a new one on your e-mail clicking on "Forgot your password?" into the User Manager page. If you don't remember your username you can click on "Forgot your username?".
Use the "Change password" tab into the User Manager page.
Perform a self-registration.