How to upgrade Samba 4 from very old version to the latest version

Question

Some bugs are annoying me in my Samba 4.4.5 (installed by building from source), and I want to upgrade it to 4.6.6 (the current last version).

I know how to build Samba from source, but I am not sure how to upgrade it correctly without losing my domain controller data (Samba is my domain controller). The documentation was not very clear about that (at least I didn't find a helpful guide).

So what is the correct way to upgrade Samba? should I download and install every single patch!? I hope not, because it is very boring and not practical solution. or is there any more efficient solution?

So generally did some body upgrade Samba from any old version to much newer version with 100% success? if yes, how?

Solution

OK I found good documentation about that. If any one has better answer or any notes, please post them.

The Update Process

Run the following steps, whether you are updating a Samba Active Directory (AD) domain controller (DC), a Samba NT4-style PDC, a Samba domain member, or a standalone installation:
Stop all Samba services.
Create a backup.
Read the release notes of skipped versions. They contain important information, such as new features, changed parameter, and bug fixes. In case you switch to new major release, read the release notes of the initial version (x.y.0) and the ones from minor versions up to the new version you will update to. For example, if you update from 4.4.4 to 4.6.2, read the 4.5.0, 4.6.0, 4.6.1, and 4.6.2 release notes.
Install the latest version over your existing one:
If you compile Samba from the sources, use the same configure options as used for your previous version. For more information, see Build Samba From the Sources.
If you update using packages, read the distribution documentation for information how to update.
Start Samba.
Start the same daemons as on your previous version:
On Samba AD DCs: samba
On Samba NT4-style PDC/BDCs: smbd, nmbd
On Samba domain members: smbd, nmbd (winbind, if used)
On Samba standalone hosts: smbd
On Samba AD DCs only: Run the Samba AD DC database check.
Check your Samba log files for errors.
Test your updated installation.

https://wiki.samba.org/index.php/Updating_Samba#The_Update_Process