SQL 2017 Standard Availability Group I am working on creating an AG on SQL Server 2017 Standard and Windows Server 2016.  I have created the failover cluster using a file share witness and everything checks out OK with the cluster.  The only issue or warnings I get are related to only using 1 NIC for each server (These are VM's with multiple NIC's).  I can connect to the SQL instance using the windows failover cluster DNS entry.  When I down one server or manually fail over the cluster, the cluster DNS entry does not update to point to the new "failed over IP"  These 2 different IP's are on 2 separate subnets.  After some time (20 minutes) the DNS entry will update to the new (failed over) IP.  I have tried to adjust the TTL setting in the cluster name DNS entry however, it changes itself back to 20 minutes.  What am I missing here?
As you don't mention it, I suspect your application is not connecting with 

MultiSubnetFailover=True


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