How can I incrementally backup a maildir to a cifs share without creating a full image each time?
I have dovecot running with some large mail accounts. The only backup available is on a Windows server.
I would prefer a solution somewhere between using rsync on the whole directory structure and creating an archive of each mail account (or even the whole dovecot mail directory).
I have considered creating a script to traverse the directory structure and create an archive of each folder if there has been any updates according to timestamp. If necessary, I could probably base64 encode all the directory names. I don't need to preserve any user permissions as the whole mail directory is using the vmail user. Are there better solutions? Do I also have to consider any maildir locking?