$ service dovecot status

dovecot: auth-worker(2769): Error: mysql(127.0.0.1): Connect failed to database (postfix): Access denied for user 'postfix'@'localhost' (using password: YES) - waiting for 125 seconds before retry

driver=mysql

default_pass_scheme=PLAIN-MD5

connect=host=127.0.0.1 dbname=postfix user=postfix password=postfix

password_query=SELECT username,domain,password FROM usuarios WHERE username='%n' AND domain='%d'

user_query=SELECT 1007 as uid, 1007 as gid, concat("maildir:/var/vmail",domain,'/',username,'/') as mail FROM usuarios WHERE username='%n' AND domain='%d'

iterate_query=SELECT username,domain FROM usuarios