[Dovecot] Mails repopping

[Simon Brereton]

> -----Original Message-----
> From: dovecot-bounces at dovecot.org [mailto:dovecot-
> bounces at dovecot.org] On Behalf Of Simon Brereton
> > -----Original Message-----
> > From: Timo Sirainen [mailto:tss at iki.fi] On Fri, 2011-09-09 at 13:07
> > -0400, Simon Brereton wrote:
> >
> > > I have a server that's been running Courier for about 6 years and
> > in
> > > all that time I think I've only ever had 1 issues where an entire
> > mail
> > > box was repopped by a webmail client.  However, since moving to a
> > new
> > > server and dovecot 4 weeks ago, I've now had the webmail client
> > repop
> > > this account 4 times (there are about 230 mails in the account).
> > >
> > > Is there a setting I need to tighten to prevent/remedy this?  I
> > have
> > > no idea if it's happening on other accounts, but this is one that
> I
> > > see.  The format is maildir.  There has been no changes to the
> > webmail
> > > client.
> >
> > dovecot -n output would have been nice. Also do you see anything in
> > error logs?
> 
> Ah.  My apologies of course.  Here it is..
> 
> mail:~# dovecot -n
> # 1.2.15: /etc/dovecot/dovecot.conf
> # OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.2 ext3
> log_timestamp: %Y-%m-%d %H:%M:%S
> protocols: imap imaps pop3 pop3s
> ssl_ca_file: /etc/ssl/keys/rhodes-ca.crt
> ssl_cert_file: /etc/ssl/keys/mail.domain.net.crt
> ssl_key_file: /etc/ssl/private/mail.domain.net.key
> disable_plaintext_auth: no
> 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_privileged_group: mailsystem
> mail_location: maildir:/var/spool/mail/virtual/%d/%n
> maildir_very_dirty_syncs: yes
> mbox_write_locks: fcntl dotlock
> mail_executable(default): /usr/lib/dovecot/imap
> mail_executable(imap): /usr/lib/dovecot/imap
> mail_executable(pop3): /usr/lib/dovecot/pop3
> mail_plugins(default): quota imap_quota
> mail_plugins(imap): 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
> imap_client_workarounds(default): outlook-idle delay-newmail
> imap_client_workarounds(imap): outlook-idle delay-newmail
> imap_client_workarounds(pop3):
> pop3_client_workarounds(default):
> pop3_client_workarounds(imap):
> pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh
> lda:
>   postmaster_address: postmaster at domain.net
>   mail_plugins: quota
>   log_path:
>   info_log_path:
>   deliver_log_format: msgid=%m: %f: %$
> auth default:
>   mechanisms: plain login
>   user: mailsystem
>   verbose: yes
>   passdb:
>     driver: sql
>     args: /etc/dovecot/dovecot-sql.conf
>   userdb:
>     driver: prefetch
>   userdb:
>     driver: static
>     args: uid=999 gid=115 home=/var/spool/mail/virtual/%d/%n
> allow_all_users=yes
>   socket:
>     type: listen
>     client:
>       path: /var/spool/postfix/private/auth
>       mode: 432
>       user: postfix
>       group: mailsystem
>     master:
>       path: /var/run/dovecot/auth-master
>       mode: 432
>       user: mailsystem
>       group: mailsystem
> plugin:
>   quota: maildir
> 
> Could you make dovecot -n munge the certificate and postmaster email
> addresses?  I'm not comfortable with that floating on the internet..
> 
> The only thing I have in the logs is 2 sessions where mail was popped
> (note, it doesn't even add up to the 183 messages in the mail box).
> But those sessions are vastly longer than the regular ones (tens of
> minutes compared to a few seconds).  Since both IPs are on the back-
> bone, that's quite a while to download 100 mails (none of which are
> over
> 
> Sep 11 21:36:25 mail dovecot: pop3-login: Login:
> user=<user at domain.com>, method=PLAIN, rip=64.88.168.84,
> lip=83.170.65.xxx, TLS Sep 11 21:36:34 mail dovecot:
> POP3(user at domain.com): Disconnected: Logged out top=0/0, retr=0/0,
> del=0/183, size=14025971 Sep 11 21:43:44 mail dovecot: pop3-login:
> Login: user=<user at domain.com>, method=PLAIN, rip=64.88.168.84,
> lip=83.170.65.xxx, TLS Sep 11 21:44:54 mail dovecot:
> POP3(user at domain.com): Disconnected: Logged out top=0/0, retr=0/0,
> del=0/183, size=14025971 Sep 11 21:52:31 mail dovecot: pop3-login:
> Login: user=<user at domain.com>, method=PLAIN, rip=64.88.168.84,
> lip=83.170.65.xxx, TLS Sep 11 22:56:01 mail dovecot:
> POP3(user at domain.com): Disconnected: Logged out top=0/0,
> retr=100/9182678, del=0/183, size=14025971 Sep 11 23:08:58 mail
> dovecot: pop3-login: Login: user=<user at domain.com>, method=PLAIN,
> rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 11 23:37:57 mail
> dovecot: POP3(user at domain.com): Disconnected: Logged out top=0/0,
> retr=75/4748674, del=0/183, size=14025971 Sep 12 00:04:11 mail
> dovecot: pop3-login: Login: user=<user at domain.com>, method=PLAIN,
> rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 12 00:04:26 mail
> dovecot: POP3(user at domain.com): Disconnected: Logged out top=0/0,
> retr=0/0, del=0/183, size=14025971 Sep 12 00:07:40 mail dovecot:
> pop3-login: Login: user=<user at domain.com>, method=PLAIN,
> rip=64.88.168.84, lip=83.170.65.xxx, TLS Sep 12 00:07:53 mail
> dovecot: POP3(user at domain.com): Disconnected: Logged out top=0/0,
> retr=0/0, del=0/183, size=14025971
> 
> 
> > If you're using the default pop3_uidl_format it'll rely on IMAP
> UIDs
> > to stay the same, and I guess it's possible that due to some other
> > problem they change (that should be logged as an error/warning
> > though).
> >
> > You could try setting pop3_uidl_format=%f, but it will cause
> everyone
> > to redownload mails. With newer Dovecot versions you could set
> > pop3_save_uidl=yes and when you think everyone's downloaded mails
> once
> > you can safely change the pop3_uidl_format.
> 
> Sorry, I'm very new to dovecot and I'm not sure I understand.  I
> presume because neither of those keys are in the dovecot -n output
> that they are as the defaults, yes?  The account is indeed accessed
> by IMAP as well (from a mobile device mostly), but I don't see
> anything fishy there either.  How could I see if the IMAP UIDs have
> changed?
> 
> Sep 11 21:20:32 mail dovecot: IMAP(user at domain.com): Connection
> closed bytes=1095/8292
> 
> Sep 11 21:26:03 mail dovecot: imap-login: Login:
> user=<user at domain.com>, method=PLAIN, rip=174.252.83.244,
> lip=83.170.65.xxx, TLS Sep 11 22:11:20 mail dovecot:
> IMAP(user at domain.com): Disconnected for inactivity bytes=725/5638 Sep
> 11 22:17:10 mail dovecot: imap-login: Login: user=<user at domain.com>,
> method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 11
> 23:12:06 mail dovecot: IMAP(user at domain.com): Disconnected for
> inactivity bytes=1471/11025 Sep 11 23:23:22 mail dovecot: imap-login:
> Login: user=<user at domain.com>, method=PLAIN, rip=174.252.83.244,
> lip=83.170.65.xxx, TLS Sep 11 23:52:52 mail dovecot:
> IMAP(user at domain.com): Connection closed bytes=1841/13679 Sep 12
> 00:08:47 mail dovecot: imap-login: Login: user=<user at domain.com>,
> method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 12
> 01:19:05 mail dovecot: imap-login: Login: user=<user at domain.com>,
> method=PLAIN, rip=174.252.83.244, lip=83.170.65.xxx, TLS Sep 12
> 02:57:01 mail dovecot: IMAP(user at domain.com): Connection closed
> bytes=2713/60026 Sep 12 02:57:01 mail dovecot: IMAP(user at domain.com):
> Connection closed bytes=2688/18635
> 
> 
> There are no errors or warnings in the mail log (I have one shared
> log file for postfix, amavis and dovecot).  Reading the notes for
> pop3_save_uidl it doesn't seem to be a dangerous option  - should I
> turn that on?  Why will it force everyone to redownload mails
> (there's nothing about it on the wiki)?
> 
> Thanks!
> 
> Simon

Any help would be appreciated.

Thanks.

Simon