On Fri, 2010-09-03 at 17:09 +0100, William Blunn wrote: > I think the only thing I had further questions on was how alternate > storage works with mdbox. > > In http://wiki2.dovecot.org/MailboxFormat/dbox it says we have > > * dovecot.map.index* files contain the "map index" > * m.* files contain the mail data > > I think I am not clear on the "dovecot.map.index* files". Is that really > just one file "dovecot.map.index", and the globby asterisk just > indicates that there may be may be old versions if the file has been > updated by being re-written?
It's the same as dovecot.index files that you see for mailboxes. There are: - dovecot.index updated once in a while (doesn't exist initially) - dovecot.index.log always, updated always first - dovecot.index.log.2 - the .log is rotated to this for a while > "dovecot.map.index*" is always stored in the primary storage? Yes. > So if we are moving mail to alternate storage, we write them into a new > "m.*" file in the alternate storage folder containing the messages we > want to move. Either a new m.* file or existing m.* file in there. > So that would mean it only really makes sense for any > given numbered "m.*" file to exist in either the primary storage or the > alternate storage but not both? Right, it's a bug if it exists in both. > So when Dovecot is wanting to find the next unused "m.*" file number, it > needs to consider files in both the primary storage and alternate storage? Yes, but it looks up the next number from index file, not by scanning what files exist.