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I've got a lot of history in email servers in the cloud (i.e. someone else's computer). I'm looking for some way to make a local backup of all that data, preferably one I could easily access/search.
There are two products I know of that do exactly what I want but they're both Windows only MailStore and MailShelf. There's apparently also a Mac only program called Horcrux. But nothing I can find for Linux.
Thunderbird is not and could not ever be considered a backup solution. There is no way within TB to know it has completed downloading mail (even assuming it ever would). This is on its own absolutely disqualifying. It's not good enough for a backup to simply hope it's done, if it worked at all (which there is no way to check in TB). Thunderbird's cache was never designed to produce authoritative backups, it's just a convenience feature.
There do seem to be a number of Linux console tools that do the first half of what I want (imapsync, imap-backup, more?) but I'm not sure how I'd access/search the mail after the messages were down. There are also enterprise products (Piler, MailArchiva) which are probably overkill, and would be a hassle to setup anyway.
I asked this question on Ubuntu's own forum several days ago but the only solution suggested was to run a local mail server and then sync the cloud accounts to that. It might work, but it seems there should be a better way.
Is anyone out there willing to share the solution they have for this problem?