To be honest, I don't like that they are so heavy. For example, Carbonio
requires a minimum of 16GB RAM, and recommends 32GB ( https://docs.zextras.com/carbonio-ce/html/requirements.html#system-requirements
)
My impression is that a mail server does not need more than 1 or 2 GB RAM.
Yes, they also manage files, calendars, etc. but these are not necessary in
my opinion, because NextCloud can do it better.
Besides, installing and updating a letsencrypt certificate is a painful
manual task ( Installing Carbonio CE with LXD :: Dashamir Hoxha / Technical Blog).
With all the scripting and tools that they have done, they still have not
automated the letsencrypt certificate!
So, I'd like to explore any other mail server alternatives, which are
easier to install and maintain, and which are lighter in
resource requirements. Could you suggest anything, based on your experience?
This post from Zimbra community may explain some of the reasons:
Basically, Zimbra is neglecting its Open Source edition, and it is becoming
more difficult to keep it up to date.
The Zimbra that I am trying to migrate is stuck on ubuntu-16, if I am not
wrong.
So, the community has tried to fork it and started Carbonio.
