Slow IMAP Auth

[Jeff Duncan-2]

Hello,

I am experiencing IMAP authentication delays when a client first authenticates, or after the last auth timeout.  There are only a handful of clients - less than 5 - using the server.  I am using a mysql database and I have verified the PAM auth is commented out.  Other than that I can't figure out what might be causing the slow authentication.  The first time a client authenticates with SSL/CRAMD5 it takes almost 20 seconds.  Does anyone have any suggestions?  My config and version is below:

mail:~# dovecot --version
1.1.11

mail:/usr/share/gallery2# dovecot -n
# 1.1.11: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.26-2-686 i686 Debian 5.0.3 ext3
log_timestamp: %Y-%m-%d %H:%M:%S
protocols: imap imaps pop3 pop3s
login_dir: /var/run/dovecot/login
login_executable(default): /usr/lib/dovecot/imap-login
login_executable(imap): /usr/lib/dovecot/imap-login
login_executable(pop3): /usr/lib/dovecot/pop3-login
mail_max_userip_connections(default): 20
mail_max_userip_connections(imap): 20
mail_max_userip_connections(pop3): 10
first_valid_uid: 6060
mail_privileged_group: mail
mail_location: maildir:/var/vmail/%d/%n
mail_executable(default): /usr/lib/dovecot/imap
mail_executable(imap): /usr/lib/dovecot/imap
mail_executable(pop3): /usr/lib/dovecot/pop3
mail_plugins(default): autocreate quota imap_quota
mail_plugins(imap): autocreate quota imap_quota
mail_plugins(pop3): quota
mail_plugin_dir(default): /usr/lib/dovecot/modules/imap
mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap
mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3
auth default:
 mechanisms: plain login cram-md5
 passdb:
   driver: sql
   args: /etc/dovecot/dovecot-sql.conf
 passdb:
   driver: sql

[Jeff Duncan-2]

I am looking into whether or not this is DNS related internally.

Sent from an iPhone

On Nov 10, 2009, at 10:18 PM, Jeff Duncan <jeff@...>  
wrote:

> Hello,
>
> I am experiencing IMAP authentication delays when a client first  
> authenticates, or after the last auth timeout.  There are only a  
> handful of clients - less than 5 - using the server.  I am using a  
> mysql database and I have verified the PAM auth is commented out.  
> Other than that I can't figure out what might be causing the slow  
> authentication.  The first time a client authenticates with SSL/
> CRAMD5 it takes almost 20 seconds.  Does anyone have any  
> suggestions?  My config and version is below:
>
> mail:~# dovecot --version
> 1.1.11
>
> mail:/usr/share/gallery2# dovecot -n
> # 1.1.11: /etc/dovecot/dovecot.conf
> # OS: Linux 2.6.26-2-686 i686 Debian 5.0.3 ext3
> log_timestamp: %Y-%m-%d %H:%M:%S
> protocols: imap imaps pop3 pop3s
> login_dir: /var/run/dovecot/login
> login_executable(default): /usr/lib/dovecot/imap-login
> login_executable(imap): /usr/lib/dovecot/imap-login
> login_executable(pop3): /usr/lib/dovecot/pop3-login
> mail_max_userip_connections(default): 20
> mail_max_userip_connections(imap): 20
> mail_max_userip_connections(pop3): 10
> first_valid_uid: 6060
> mail_privileged_group: mail
> mail_location: maildir:/var/vmail/%d/%n
> mail_executable(default): /usr/lib/dovecot/imap
> mail_executable(imap): /usr/lib/dovecot/imap
> mail_executable(pop3): /usr/lib/dovecot/pop3
> mail_plugins(default): autocreate quota imap_quota
> mail_plugins(imap): autocreate quota imap_quota
> mail_plugins(pop3): quota
> mail_plugin_dir(default): /usr/lib/dovecot/modules/imap
> mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap
> mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3
> auth default:
> mechanisms: plain login cram-md5
> passdb:
>   driver: sql
>   args: /etc/dovecot/dovecot-sql.conf
> passdb:
>   driver: sql
>
>

[Timo Sirainen]

On Tue, 2009-11-10 at 22:18 -0500, Jeff Duncan wrote:
> I am experiencing IMAP authentication delays when a client first authenticates, or after the last auth timeout.  There are only a handful of clients - less than 5 - using the server.  I am using a mysql database and I have verified the PAM auth is commented out.  Other than that I can't figure out what might be causing the slow authentication.  The first time a client authenticates with SSL/CRAMD5 it takes almost 20 seconds.  Does anyone have any suggestions?  My config and version is below:
..
>  passdb:
>    driver: sql
>    args: /etc/dovecot/dovecot-sql.conf
>  passdb:
>    driver: sql

Well, you have two passdb sqls.. I'm not really sure what it does when
the other one doesn't have args. It anyway isn't a good idea.