Archiving mail, how to be?

Question

Backup

Good afternoon, I would like to ask how and what you use to archive mail.
I found a couple of programs that seem to do what they need. But almost all are crooked or do not fit.
What I have tested.
MailStore Home - Of the minuses , there is only under Windows, during testing 1 time I broke the entire archive so that I had to erase everything and make a backup again. There is no way to monitor boxes. The firm was recently sold and the future is unknown. From the pros , it works more or less stably, saves attachments, there is a search and export.
MailStore Server is the same as MailStore Server but can monitor mailboxes by itself and costs ~300€ + 70€ per year for 5 users.
MailArchiva- For free, if there are no more than 20 boxes. From the minuses , as I understand it, it saves only everything in the domain, so you can’t just save boxes on different services (or I didn’t understand how). Of the benefits You can install anywhere, there are packages for lin, win, solaris. Or just download .wad and install it on your Tomcat server. There is a web interface and it monitors boxes.
mailpiler - open source, there is a web-gui. There is a search in the GUI, but it does not show the entire box.
I also found Barracuda message archiver , but it's not even worth the price there.
I'm looking for a way to archive ~10 mailboxes on my Linux server and not go crazy.

Answer 1

To be honest, this is not the first time I have faced this issue myself. Unfortunately, I have not seen really simple , convenient and free programs of this kind.
The task seems to be trivial: to make a backup of mail folders from one server, and then deploy it to another. But doing it through email clients is somehow... a crutch.
However, I liked a couple of things:

• IMAPSize - was originally planned as a utility for evaluating the size of mailboxes on an IMAP server, but in the process it acquired various functionality, including a backup and restore function. The program is old (February 2009), has a version only for Windows. But it's free and, most importantly, it works. And on Mac it runs through CrossOver, which is also very pleasing. On Linux, respectively.
  
• imapsync is a utility for transferring mail from one server to another (without intermediate backup). Created in the early 2000s and maintained to this day. It is written in Perl, has compiled versions for Windows and Mac, and is also available in source code (you can put it on any unix server). Paid.