What is the right order when updating Mac OS and Mac Server?

Hello,

If you are basically using your Mac Mini as file server I highly recommend to do a fresh install via usb stick and migrate the services manually. File sharing is easy to set up and you avoid problems related to the update process. First backup your servers boot drive via tools like SuperDuper to have a working copy. Put a fresh file system on your boot hd and install MacOS Sierra via usb installer. Next download and install Server 5.2 via app store. Configure the file sharing service. Thats it. It takes around 4 hours + time for backup. If you need to recreate lots of user accounts and permissions (> 20) a fresh install might be not your best option but for me it is best practice.

HTH

Enno

While as discussed by OnkelEnno a lot of people choose rather to build completely fresh systems and migrate the data if you are going to do an upgrade then actually there is no choice in the order.

Older versions of OS X nee macOS will not run newer versions of Server.app you therefore have to first upgrade the version of OS X and then upgrade the version os Server.app.

What is annoying and confusing is that the Mac App Store will often show both an update to OS X and an update to Server.app at the same time with the Server.app being a version which requires the update to OS X. You might expect to be able to do both updates at the same time but it simply does not work. In my opinion this is broken behaviour.

With SoftwareUpdate as opposed to the Mac App Store Apple have for years correctly only listed updates suitable for your currently running version of OS X, once you have updated OS X it would recheck for any further updates and would then list them. So in theory it should not list the newer Server.app update until the OS X update has first been installed and thereby avoid confusion.

Note: It is a good idea to keep copies of previous versions of Server.app as these cannot be redownloaded later. I strongly recommend making a ZIP file of them so OS X does not see them on your hard drive and get confused. I have a complete set thereby allowing me if I need to setup a Server running Lion, Mountain Lion, Mavericks, etc. as needed.

Again many people would go the route of doing a completely fresh build and then migrating data and settings. However I would suggest making a full backup in the form of a clone and then upgrading directly to 10.12.

If this does not work you could restore a copy of the clone (you still need to keep a safe copy) and then try the 10.10 to 10.11 and then 10.11 to 10.12 route. If that does not work then you will pretty much need to give up and do the fresh build and data migration route.

There is no absolute rule to this, Apple would say that you should be able to upgrade over an existing setup. I suspect the possibility of failure might be down to what services you are using and what settings you might have used. Services I feel more likely to be troublesome would be Wiki and ProfileManager which use PostgreSQL and for which Apple have made significant changes to themselves.