Am 2018-04-09 00:55, schrieb Steve Atkins:
Will a simple backup of all the files of an multi-dbox give me a consistent state when I recover, or do I need to do something (e.g. lock writes to the mailbox) while I run a backup?
If you are doing this backup with a fully operational mail storage: no, it won't. The reason is quite simple: mdbox saves the data of an email in several files, so there's a good chance that those files might slightly change during backup, while with Maildir all necessary data for the restore is stored in the file names.
If you want to do a consistent backup, you do need file system snapshots and should make sure that this snapshot is consistent or to turn off the mail store during backup completely.
But just doing rsync on the fly as with Maildir is just begging on your side to run into problems sooner or later...
-- Greetings, Marc