Basic Availability Groups can do Automatic Failover ? , Is Windows Clustering a Requirement for BAG

1. I will be using SQL Server 2017 the latest version out ,
2. This version does not supports Mirroring as that was marked deprecated with the release of SQL Server 2014
3. Now I don’t or rather say I will not be using Enterprise Edition of SQL Server for AADConnect DB
4. Now what options I am left with to setup high availability for AADConnect DB
5. I have checked there is a feature of “Basic Availability Group” (BAG) available with SQL Server 2016/2017 versions
6. I have doubts or need to clear understanding on the usage of this BAG
   1. Does this provide for Automatic Failover
   2. Does this require Windows Clustering and Witness for Automatic failover or not
7. I have checked few articles on this
   1. Top 7 Questions about Basic Availability Groups

https://blogs.technet.microsoft.com/msftpietervanhove/2017/03/14/top-5-questions-about-basic-availability-groups/

1. Basic Availability Groups (Always On Availability Groups)

https://docs.microsoft.com/en-us/sql/database-engine/availability-groups/windows/basic-availability-groups-always-on-availability-groups?view=sql-server-2017

There are Limitations mentioned on this link, however does not mention anything on Windows Clustering or Witness requirements

Limitations

1. Basic availability groups use a subset of features compared to advanced availability groups on SQL Server 2016 Enterprise Edition. Basic availability groups include the following limitations:
2. Limit of two replicas (primary and secondary).
3. No read access on secondary replica.
4. No backups on secondary replica.
5. No integrity checks on secondary replicas.
6. No support for replicas hosted on servers running a version of SQL Server prior to SQL Server 2016 Community Technology Preview 3 (CTP3).
7. Support for one availability database.
8. Basic availability groups cannot be upgraded to advanced availability groups. The group must be dropped and re-added to a group that contains servers running only SQL Server 2016 Enterprise Edition.
9. Basic availability groups are only supported for Standard Edition servers.
10. Basic availability groups can not be part of a distributed availability group.

1. Prereqs, Restrictions, Recommendations - Always On Availability Groups

https://docs.microsoft.com/en-us/sql/database-engine/availability-groups/windows/prereqs-restrictions-recommendations-always-on-availability?view=sql-server-2017

However this link clearly lists out that Windows Clustering is a requirement for AlwaysOn Availability Group (Basic Availability Group is based or rather say are subset of this only)

1. Availability Modes (Always On Availability Groups)

https://docs.microsoft.com/en-us/sql/database-engine/availability-groups/windows/availability-modes-always-on-availability-groups?view=sql-server-2017

An Extremist