Basic Concepts

Backup Policies

A backup policy is a set of rules for backing up data, including the policy name, policy status, execution time of backup jobs, backup period, and retention rules. The retention rules specify the retention duration and number of retained backups. After an ECS is associated with a backup policy, it can be automatically backed up according to the backup policy.

Backup

A backup is a copy of the original data that is backed up. A backup is used to restore the original data. It can be generated in a one-off or periodic method.

CSBS supports one-off backup and periodic backup. A one-off backup job is manually created by users and takes effect for only one time. Periodic backup jobs are automatically driven by a user-defined backup policy.

• The name of a one-off backup is manualbk_xxxx. It can be user- or system-defined.
• The name of a periodic backup is assigned automatically by the system. The name of a periodic backup is autobk_xxxx.

Instant Restore

Instant Restore restores ECS data and creating images for backups, which is much faster than normal restoration.

Backups generated before Instant Restore is enabled do not support instant restoration. To use the feature, perform a full backup and select Enable next to Full Backup when creating the backup. For details, see . After Instant Restore is enabled, manual backups for ECSs that have not been backed up automatically support instant restoration, without requiring the selection of Enable next to Full Backup.

No matter whether an ECS has been backed up or not, its automatic backups generated after Instant Restore is enabled do not support instant restoration, unless you manually perform a full backup on it.

Application-Consistent Backup

There are three types of backup consistency:

• Inconsistent backup: Files and disks are backed up at different points in time.
• Crash-consistent backup captures data existing on disks upon backup and backs up files and disks at the same point in time, without backing up memory data and quieting application systems. Backup consistency of application systems is not ensured. Though the application consistency is not ensured, disks, such as chkdsk, will be checked upon operating system re-startup to restore damaged data and log rollback will be performed on databases to keep data consistent.
• Application-consistent backup backs up files and disks at the same point in time, including memory data, to ensure application system consistency.

Project

Projects are used to group and isolate OpenStack resources (computing, storage, and network resources). A project can be a department or a project team. Multiple projects can be created for one account.