Backup and disaster Recovery for database backup SQL Server

The major server hardware vendors (IBM,HP, etc.) provide good data protection policies (hardware or software). A well known RAID disk array (redundant array of independent disks) is a good way to protect data. In the case of SQL Server , a detailed data backup plan can be developed through a maintenance plan.

Data backup strategy (full backup, differential backup and transaction log backup)

Data backups are services for data recovery, so before you set up a data backup plan, consider whether you can take advantage of the backup's valid recovery data (within the time allowed by downtime). You should also consider the RPO allowed by the system (Recovery point objective, after a disaster occurs, The point at which the system or data must be recovered, RTO (Recovery time objective), which is how long it takes to restore the system or data to a functioning state when a system recovery tool or solution is used after a disaster occurs.

There are three commonly used backup schedules:

(1). Only full backup

The time period between two full backups fails and the data is lost and can only be recovered to the last fully backed up data.

(2). Full Backup + log backup

By adding a log backup between full backups, you can reduce the backup point to a smaller granularity. You can do a full backup every day, every one hours or half an hour to do a log backup. In such a case, if a failure occurs at 23:59, a full backup+ need to be restore 23 Transaction log backup, the operation recovery time will be more long.

(3). Full backup + differential backup + log backup

A differential backup (differential backup) is added between full backups, and a log backup is between the differential backups.

As to which backup strategy to choose, it should be flexibly applied according to the actual situation (RTO, RPO, Server loading, etc.).