[Dovecot] dovecot-auth restaring and caching

[Angel L. Mateo]

Hello,

	I'm trying to configure dovecot (2.0.13) to cache user and pass dbs. 
This a mail server whose purpose is only to deliver messages through 
dovecot lda. My users are in a ldap server.

	So I have configure auth_cache_size (with 20MB) and auth_cache_ttl 
(with 1 day). I have checked that caching is being done, and it is. If a 
send a message to a user, dovecot looks for it in my ldap server. If 
then I send another, then it uses cache information.

	The problem I'm having is that if I have no activity in the server, 
dovecot stops its auth process and when another message is received, it 
restarted it, but with an empty cache.

	This is the auth log for the first message:
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: Loading modules from 
directory: /usr/lib/dovecot/modules/auth
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: Module loaded: 
/usr/lib/dovecot/modules/auth/libauthdb_ldap.so
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: master in: 
USER#0111#011amateo#011service=lda
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: prefetch(amateo): passdb 
didn't return userdb entries, trying the next userdb
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: userdb-cache(amateo): miss
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: ldap(amateo): user search: 
<search base and filter> 
fields=irisMailbox,homeDirectory,uidNumber,gidNumber
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: ldap(amateo): result: 
uidNumber(uid)=XXXXX gidNumber(gid)=XXX homeDirectory(home)=XXXXXXXXXX
Mar 22 10:29:41 lynx10 dovecot: auth: Debug: master out: 
USER#0111#011amateo#011uid=XXXXXX#011gid=XXX#011home=XXXXXXXXXXXX

	And this is the second one, just after a few minutes:
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: Loading modules from 
directory: /usr/lib/dovecot/modules/auth
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: Module loaded: 
/usr/lib/dovecot/modules/auth/libauthdb_ldap.so
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: master in: 
USER#0111#011amateo#011service=lda
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: prefetch(amateo): passdb 
didn't return userdb entries, trying the next userdb
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: userdb-cache(amateo): miss
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: ldap(amateo): user search: 
<search base and filter> 
fields=irisMailbox,homeDirectory,uidNumber,gidNumber
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: ldap(amateo): result: 
uidNumber(uid)=XXXXX gidNumber(gid)=XXX homeDirectory(home)=XXXXXXXXXXX
Mar 22 10:41:03 lynx10 dovecot: auth: Debug: master out: 
USER#0111#011amateo#011uid=XXXXX#011gid=XXX#011home=XXXXXXXXXX

	This is my configuration:

root at lynx10:/etc/dovecot/conf.d# doveconf -n
# 2.0.13: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-4-amd64 x86_64 Ubuntu 10.04.4 LTS
auth_cache_size = 20 M
auth_cache_ttl = 1 days
auth_debug = yes
auth_verbose = yes
hostname = lynx10
passdb {
   args = /etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
plugin {
   sieve = ~/.dovecot.sieve
   sieve_dir = ~/sieve
   sieve_extensions = +imapflags
   sieve_max_redirects = 15
}
postmaster_address = postmaster at um.es
protocols = " imap lmtp pop3"
service auth {
   unix_listener auth-userdb {
     mode = 0666
   }
}
ssl_cert = </etc/ssl/certs/dovecot.pem
ssl_key = </etc/ssl/private/dovecot.pem
userdb {
   driver = prefetch
}
userdb {
   args = /etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
protocol lmtp {
   mail_plugins = " sieve"
}
protocol lda {
   mail_plugins = " sieve"
}

	Any idea?

-- 
Angel L. Mateo Martínez
Sección de Telemática
Área de Tecnologías de la Información       _o)
y las Comunicaciones Aplicadas (ATICA)      / \\
http://www.um.es/atica                    _(___V
Tfo: 868887590
Fax: 868888337