This is multi part article. Please refer the Part 1 Article before you begin this article so that you will not get confused to understand and follow further.
Once Computer restarted the Server 2016, Now you can see that AD FS Management is available. Now Click on it and open the AD FS Management
But if you see, AD FS on Server 2016 is not showing anything here. Why??. Reason is the behavior of the farm is Server 2012 and only the Server 2012 ADFS nodes can manage the farm.
If you run the command Get-AdfsSyncProperties in the server 2016, You can that PrimaryComputerName is ADFS.Windowstechpro.com which is Server 2012 ADFS Server and the Server 2016 Role is SecodaryComputer. Hence it will act as a simple ADFS Server and can take connections and respond. wherein it cannot give any Server 2016 features.
If you run the same Get-AdfsSyncProperties in the Server 2012, You will see that Role is Primarycomputer.
Phase 3: Moving FBL to Server 2016
Step 1: Before we move FBL to Server 2016, We need to make Server 2016 as PrimaryComputer so that AD FS Server 2016 will get an option to manage.
Run the below PowerShell command on Server 2016 ADFS Node to make AD FS Server 2016 as PrimaryComputer
Set-AdfsSyncProperties -Role PrimaryComputer
Run the below command on Server 2012 R2 Node
Set-AdfsSyncProperties -Role SecondaryComputer -PrimaryComputerName adfs2016.windowstechpro.com
Here, Adfs2016.windowstechpro.com is the Server 2016 ADFS Server Name
Once moved the primary to Server 2016, if you open ADFS management in server 2012, you will get the below message.
And the meantime, in server 2016, you can now able to open AD FS Management console and it is loaded completely
In Server 2016 run the below command to get the ADFS Farm Inforation
Get-AdfsFarmInformation
Since it is not going to show you the server 2012 nodes, you will get only the server 2016 nodes and FBL level is 2012 R2 which is 1
Install Server 2016 ADFSProxy servers and migrate all the nodes to server 2016 and remove adfs server 2012 R2 Nodes. ADFS Server 2016 installations as same as how to install Server 2012 ADFSProxy Servers. Please refer the article to know how to install ADFSProxy Servers.
Step 2: Removing ADFS 2012 R2 Servers from the ADFS farm:
Open Server Manager—Manage— Click on Remove Roles and FeaturesÂ
Click on Next
Click on Next
Uncheck the Active Directory Federation Services and Click on Next
Click on Next
Click on Remove
Restart the Computer and you can see that ADFS role is removed from the server. Follow the same and remove all the Server 2012 ADFS Nodes from the Farm post you added Server 2016 nodes in the farm and all are working as expected.
If you run the below command again on Server 2016, You still see that the farm is running on FBL 1
Get-AdfsProperities | Select CurrentFarmBehavior
Step 3: Upgrading Farm to FBL Server 2016
Now run the below command to upgrade the Farm behavior level to Server 2016
 Invoke-AdfsFarmBehaviorLevelRaise
Note: Don’t run this command if you have any Server 2012 Nodes in ADFS or ADFSProxy(WAP) farms.
You can see that ADFS Farm is getting upgraded and all the Server 2016 features are getting enabled for the ADFS Farm
Okay.. The upgradation has been completed successfully.
Run the below command to see current FBL Status
Get-AdfsProperities |Select CurrentFarmBehavior
 Now you can see CurrentFarmBehavior value is 3 which is AD FS 2016
Also can see now new features of AD FS 2016
Login in to IDP Initiated page and check all the login process is working well
Click on Sign in and provide the credentials
You can see sign in successful and all ADFS 2016 servers are healthy and working fine as expected.
I have seen other fellow folks are asking for adprep for Forest and domain. Ideally it is not required but yes we can do it so that you will get all the new values added to the forest for Server 2016 ADFS Features.