Recovery requirements for SQL on EC2

Both backup and recovery of MS SQL on EC2 have specific storage requirements.

For general prerequisites and requirements for MS SQL on EC2, see Getting Started with Clumio for Microsoft SQL on EC2.

For information on backup storage requirements, see Backup Requirements for MSSQL on EC2.

Recovery model requirements for MS SQL databases

A SQL database can be configured with one of the three recovery models: simple recovery model, full recovery model and bulk-logged recovery model. While full and incremental database backups are supported with all recovery models, transaction log backups can only be taken when the database is in full recovery model or bulk-logged recovery model.

Clumio provides two types of recovery operations:

• Point-in-time (PITR) recovery allows you to recover the database to a specific point in time. This requires transaction log backups and is only available for databases with full recovery model or bulk-logged recovery model.
• Full database recovery allows you to recover a database to the last complete backup. Transaction log backups are not required to perform this type of recovery.

Restore storage requirements

Refer to the table below for the storage requirements to restore Microsoft SQL databases in Clumio. The term "space" in the table refers to the free disk space required on the target restore location, equivalent to the disk space used by the database about to be recovered.

	Overwrite database	Restore as new database
Full database recovery	1x space	1x space
Point-in-time recovery	1x space	1x space

You can restore a SQL Server database in the following ways:

• Full recovery of a database by overwriting the existing database.
• Full recovery of a database as a new database.
• PITR recovery of a database by overwriting the existing database to a specified point-in-time.
• PITR recovery of a database as a new database.

1x disk space is needed in all cases to copy over the snapshot files from Clumio for a restore operation. This free space must be on the target location where the database is to be restored. For example, consider a database with a size of 10GB:

• 1x means that free space of 10GB is required on the disk/drive where the database is to be restored.

Best practices and recommendations

When recovering as a new database, if the target host has the same file paths (DB, Log) as the source database, this causes path conflict and the restore may fail. Clumio recommends that you customize file paths where restored files have to be placed.