I used dovecot Auth daemon for postfix SMTP Auth. I saved clear password to OpenLDAP, then I set up that as the password will be used.

There ware no trouble when authentication had sucessed. But when authentication failed by using "CRAM-MD5", it caused increasing memory allocation of dovecot auth daemon.

In case of using "PLAIN" or "LOGIN", there were no problem even if authentication had failed.

I got same result on dovecot-2.0.9(RHEL6) and dovecot-2.2.13.

Does anyone know similar case?

I tried restarting dovecot Auth daemon by using service_count parameter in service auth settings. When authentication failed, message on postfix was as follows:

** 535 5.7.8 Error: authentication failed: "CRAM-MD5 string"

When authentication failed and restarting dovecot auth daemon at the same time, message on postfix was changed as follows:

** 535 5.7.8 Error: authentication failed: Connection lost to authentication server

It looks like that the failed authentication request is suspended by restarting auth daemon.

-- config (10-auth.conf) auth_mechanisms = plain login cram-md5

-- config (10-master.conf) service auth { executable = auth

unix_listener /var/spool/postfix/private/auth { mode = 0666 user = postfix group = postfix } }

-- auth-ldap.conf.ext passdb { driver = ldap

args = /etc/dovecot/ldap-passdb.conf.ext }

-- ldap-passdb.conf.ext host = xxx.xxx.xxx.xxx dn = LDAP Manager DN dnpass = Manager DN password base = ou=mail,dc=xxxxxx,dc=xx scope = subtree pass_attrs = mailID=user,mailClearPassword=password pass_filter = (mailID=%u) auth_bind = no default_pass_scheme = plain

Thanks.

-- Kenji Tonami