I am very confused with postfix-cyrus-imap-mysql-sleepycatDB4 auth progress....

[Temp]

Hi,  all

I install postfix 2.0.4  cyrus-imapd 2.1.12  cyrus-sasl 2.1.12 and DB 4.1.25
by tarball package in Redhat 7.2, with mysql original rpm of rh 7.2.

I followed the article
http://www.delouw.ch/linux/Postfix-Cyrus-Web-cyradm-HOWTO/html/index.html
and now I can receive email by a defaut account "cyrus" but
every time postfix denied to send email by smtp-auth with sasl.
and that is the logs:

Mar 13 08:23:53 mx postfix/smtpd[11617]: warning: unknown[192.168.0.3]: SASL
LOGIN authentication failed
Mar 13 08:23:54 mx postfix/smtpd[11617]: lost connection after AUTH from
unknown[192.168.0.3]

and now I am very much confused with the auth progress,
what is the usage of sleepycat DB4??
and is DB4 a copy of username and password ?
and what is the usage of sasl ? a cache of username and password
in order to reduce the works of mysql?
or just a hiberarchy between mysql and postfix?

and is there a article for whole auth progress for postfix ?
I am confused with so many path---
for example:
hash:/...path...
mysql:/...
file:/.....
and even something else...
what is the working progress ??
and what is the ranking of alias and
local and virtual and destination....
these concepts drive me mad.


and following is my mysql tables content:

accountuser table:
+----------+---------------+--------+-------------+
| username | password      | prefix | domain_name |
+----------+---------------+--------+-------------+
| cyrus    | f9/8ICFGnvzis | hehe   | test.com  |
+----------+---------------+--------+-------------+


alias table:
+------------+------+----------+--------+
| alias      | dest | username | status |
+------------+------+----------+--------+
| test.com | NULL | cyrus    |      1 |
+------------+------+----------+--------+

virtual table:
+------------+------+----------+--------+
| alias      | dest | username | status |
+------------+------+----------+--------+
| test.com | NULL | cyrus    |      1 |
+------------+------+----------+--------+

domain table:
+-------------+--------+-------------+-------+-----------+
| domain_name | prefix | maxaccounts | quota | transport |
+-------------+--------+-------------+-------+-----------+
| test.com | hehe   |          40 | 24000 | cyrus     |
+-------------+--------+-------------+-------+-----------+


Thanks for your attention.