Doubt with role creation

Hi

I'm trying  to create a new role doing:
# CREATE ROLE db_admin WITH CREATEDB CREATEROLE CREATEUSER PASSWORD 'password';
CREATE ROLE

If I check the roles, the new one is there:
postgres=# Select rolname from pg_roles where rolname = 'db_admin';
rolname   
---------------
pele_db_admin
(1 fila)

The problem is that when I try to enter psql with this user I get the following:

postgres@linux> psql -U pele_db_admin -W
Password for user pele_db_admin:
psql: FATAL:  la autentificación Ident falló para el usuario «pele_db_admin»

which translated is: psql: FATAL:  Ident authentication failed for user «pele_db_admin»

Why is this happening and how could I avoid it?

May be users and roles are not the same and I must create a user called pele_db_admin?

Thanks in advance.

Best regards,
M