Cyrus with a NFS storage. random DBERROR

David Lang david.lang at
Fri Jun 8 23:45:56 EDT 2007

On Sat, 9 Jun 2007, Rob Mueller wrote:

> So - added is a new option "uuidmode" in imapd.conf. Set it to md5 and you
> will get UUIDs of the form: 02(first 11 bytes of the MD5 value for the
> message) which takes up the same space, but allows pretty good integrity
> checking.
> Is it safe? - we calulated that with one billion messages you have a one in
> 1 billion chance of a birthday collision (two random messages with the same
> UUID). They then have to get in the same MAILBOXES collection to sync_client
> to affect each other anyway. The namespace available for generated UUIDs is
> much smaller than this, since they have no collision risk - but if you had
> that many delivering you would hit the limits and start getting blank UUIDs
> anyway.

does the IMAP spec specify how large a UUID can be?

David Lang

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