[Imap-uw] New mix format and loss of all incoming mail !

[Mark Crispin]

There was a problem in 2006j2 in which a rewrite of the index file could 
fail if, during the course of the rewrite, some other process grabbed the 
disk space that was previously occupied by the rewrite.  Since an empty 
index file is equivalent to "no messages", if a subsequent process opens 
the mailbox the checkpoint could conceivably delete the data files.

This situation should be remedied in 2006k.  2006k will now overwrite the 
existing data on the index file.  This may still fail, as some systems 
won't let you overwrite existing data in a disk full or quota exceeded 
situation.  But it should leave some data behind.

I am considering a redefinition of the mix format to require a sequence 
record in all files.  Thus, an empty file would be considered "corrupt 
mailbox" rather than "no data".  This won't happen in the 2006 series; I 
am trying to bring 2006 to a close and this redefinition would be an 
incompatibility.

In any case, if your're still running 2006j2 you should upgrade to 2006k. 
I hope that the final version of 2006k (and the final version of 2006 
series) will be out soon; but for now the development snapshot of 2006k is 
in every way superior to 2006j2.

On Wed, 3 Oct 2007, dunric29a at atlas.cz wrote:

> UW-IMAP 2006j2

I've encountered very dangerous UW-Imap behaviour when there is no enough 
free space on disk and there is a new incoming mail (delivered to inbox by 
dmail), all .mix files from Inbox directory are erased !! I couldn't 
believe my own eyes. It was discovered at 4 users mailboxes using new .mix 
format. Mbx mailboxes left untouched. Fortunately there are daily backups 
so most of lost emails was recovered.

Could anybody else confirm this issue ? Is there already some hot-fix available ?

Thx in an advance.

David
> ------------------------------------------
>
> http://mail.atlas.cz/wapmail/

-- Mark --

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