Difference between High Availability and Disaster Recovery for SQL Server

1. SQL Server High Availability (HA) :
It is the technology that could be used to provide 100% service availability and 24×7 up-time by using extra and backup components like a copy of the database at the same location.

Benefits of High Availability :
Keeping databases online from the circumstances that might take the primary SQL Server production system offline something like a momentary glitch or an unexpected server reboot.

Limitation of High Availability :
Not useful in circumstances like the physical server running the primary SQL Server instance has a failure or your data center losses power for an extended period due to fire or flood or hurricanes, etc.


2. SQL Server Disaster Recovery (DR) :
It is the technology that could be used to provide 100% service continuity and minimizing the downtime through extra and independent components in a different location.

Benefits of Disaster Recovery :
No system is fully invulnerable. Things happen like the physical server running the primary SQL Server instance has a failure or your data center losses power for an extended period due to fire or flood or hurricanes, etc. It is important to secure that SQL Server database that could be recovered in a timely and efficient manner. Disaster Recovery (DR) is the technology that could be used here.

Difference between High Availability and Disaster Recovery for SQL Server :

Features	High Availability (HA)	Disaster Recovery (DR)
Goal	Service Availability	Service Continuity
Process	Automatic	Manual
Infrastructure	Single Location	Multiple Location
Intention	Retaining Service	Retaining Data
Fail-over Clustering	Yes	No
Database mirroring	Synchronous	Asynchronous
AlwaysON Availability Group	Yes (In Same Location)	Yes (In Different Location)
Log Shipping	Yes (In Same Location)	Yes (In Different Location)
Replication	Yes (In Same Location)	Yes (In Different Location)