High Availability (HA) – Keeping your database up 100% of the time with no data loss during common problems. Redundancy at system level, focus on failover, addresses single predictable failure, focus is on technology. SQL Server IaaS would handle this with:
- Always On Failover cluster instances
- Always On Availability Groups (in same Azure region)
- SQL Server data files in Azure
Disaster Recovery (DR) – Protection if major disaster or unusual failure wipes out your database. Use of alternate site, focus on re-establishing services, addresses multiple failures, includes people and processes to execute recovery. Usually includes HA also. SQL Server IaaS would handle this with:
Log Shipping
Database Mirroring
Always On Availability Groups (different Azure regions)
Backup to Azure
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