[Dovecot] Bug when a duplicated file is found

[Robert Schetterer]

Am 25.02.2013 11:41, schrieb Angel L. Mateo:
> Hello,
> 
>     Last days we had to restore some mailboxes from backup. Our
> mailboxes are in maildir format and during restore, some duplicated
> files appeared. The situation is:
> 
> * A user has messages in his new directory when the backup is made
> * In some moment after the backup is done, the user accesses to his
> mailbox, so the message is move to the cur directory.
> * We restore his mailbox directly to his maildir path, so the message is
> now at new directory too.
> 
>     When this happens, dovecot detect it and it renames one of the
> files. This is the reported log:
> 
> Feb 13 23:08:05 myotis31 dovecot: imap(<user>): Warning: Fixed a
> duplicate:
> /home/alumnos/59/122559/Maildir/cur/1360169810.M670208P13643.myotis31,S=6282,W=6409:2,
> -> 1360793285.M721935P29136.myotis31
> 
>     The problem with this is that we are using zlib plugin so messages
> are compressed. When the rename is done, the rename is to a name without
> the S=XXXX field (neither the W=XXX, although this field is less
> sensible), so the result is that user's can't access to any message
> after this one.
> 
>     I think than in this situation, rename one of the files is a good
> solution (although it provokes duplicate mails, but this an
> expected/acceptable situation after the restore), but the rename should
> maintain the S= and W= fields (and even other maildir flags).
> 

how you do the backup, dsync , rsync ???
perhaps you can avoid problems restore mail to another new named mailbox
like restore.orig.name at somedomain.example, then the user himself or
supporter, may  copy restored mails himself to the orig mailbox or might
be better in some subfolder i.e restore of the orig mailbox


Best Regards
MfG Robert Schetterer

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