[Dovecot] Dovecot Ldap Problem

[Timo Sirainen]

On Tue, 2010-08-10 at 18:13 +0550, Aravind Divakaran wrote:
> > 
> > Dovecot never disconnects from LDAP server. You're using
> > passdb/userdb ldap and not pam_ldap, right?
> 
> I am using passdb/userdb ldap not pam_ldap.

My googling shows:

"It means there are too many operations active on the given connection,
so further operations on that connection will be queued until some of
the active operations complete."

Maybe you need to reduce this:

/* Maximum number of pending requests before delaying new requests. */
#define DB_LDAP_MAX_PENDING_REQUESTS 128

I don't actually know what OpenLDAP's limit is.. Anyway, if so many
requests are being queued, it sounds like you're getting more
authentication attempts than your server(s) can handle in time. Try
enabling Dovecot's auth cache?
http://wiki.dovecot.org/Authentication/Caching