Readable secondary replicas can serve reports away from a SQL Server primary; learn routing, lag, licensing, and query differences to test.
Availability Groups or Failover Cluster Instances
Availability groups or failover cluster instances protect different SQL Server boundaries; compare data copies, shared storage, failover, and cost.
MultiSubnetFailover: Why Clients Time Out After an AG Failover
Diagnose an AG failover timeout with listener DNS, MultiSubnetFailover, RegisterAllProvidersIP, HostRecordTTL, and client-driver checks.
Testing a Failover Before You Need One
Testing a failover reveals connection, data, job, and recovery gaps before an outage; learn to plan a SQL Server drill and record the result.
Monitoring Availability Group Health
Monitor availability group health through replica connection state, database synchronization, send and redo queues, and failover readiness checks.
Patching an Availability Group in the Right Order
Patching an Availability Group safely means updating secondaries first, checking synchronization, failing over, and updating the old primary.