[Dovecot] dovecot-uidlist: Duplicate file entry at line

[Timo Sirainen]

On Thu, 2010-09-02 at 19:21 +0200, Luca Palazzo wrote:
> Hi All,
> we are experiencing another strange problem after upgrading to 2.0.1 
> from 1.2.
> 
> Many people's client aree-retrieving mail from server due to some 
> problem with dovecot-uidlist file.
> Looking at log file seem that all file content is sometime duplicated 
> and appended to the and of same file.
> It look as another process was accesing and trying to modify uidlist table.

I've heard of some dovecot-uidlist problems, but haven't really figured
out anything that could be wrong.. I guess there's no way you can
reproduce this? Does happen to same user more than once? How many users
is "many"? Does this happen only/mainly to some specific mailboxes
(INBOX, Trash)? Does this happen to more than one same user's mailbox at
the same time? Does this happen to different users around the same time?

> Our setup has a load balance (dovecot director) and three backend 
> server. All of them use 2.0.1.

How did you do it before v2.0?

The maildir code hasn't changed much since v1.2. Hmm. Except that
maildir filenames are now tried to be preserved when copying, so copying
messages elsewhere and back does sound like it could cause this
(although there is code to prevent it)..