[Dovecot] director's imap/pop3 login timeout

Hello,

We have two (load balanced) director servers in front of 4 dovecot 

backend servers.

Yesterday we had a problem at backend servers for some users (our SSO 

was down, so IMAP users couldn't authenticate) and this triggered a problem in director servers where almost nobody could open a new session.

In our director's logs I could see errors like this:

Mar 20 20:52:47 myotis41 dovecot: imap-login: proxy(<user>): Login failed to 155.54.211.162:143: [UNAVAILABLE] Temporary authentication failure. [myotis32:2013-03-20 19:52:47]

So, it seems it was trying to authenticate for 1 hour, after that it 

timed out the login.

But this timeout is too long. Is this a director timeout? Or a backend 

timeout? How can I reduce it?

-- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868889150 Fax: 868888337