After you back up an Elastic Compute Service (ECS) instance, you can quickly restore the ECS instance, clone a new ECS instance, or create a new ECS instance across availability zones. This topic describes the differences between the ECS instance backup feature of Cloud Backup and the snapshot service.
We recommend that you do not use the ECS instance backup feature and the snapshot service for the same disk at the same time. This prevents conflicting execution time of snapshots. You can select a backup method based on your business requirements.
Snapshot service
The Alibaba Cloud snapshot service is an agentless backup service that allows you to create crash-consistent snapshots for all disk categories to back up or restore an entire disk. The snapshot service is an effective disaster recovery solution and can be used to back up data, create images, and implement disaster recovery for applications. For more information, see Overview.
ECS instance backup
The ECS instance backup feature of Cloud Backup allows you to manage the data on ECS instances based on disk snapshots. Cloud Backup provides automatic backup policies for ECS instances and a GUI console. In the Cloud Backup console, you can configure backup or restoration parameters. You can also perform restore, clone, and disaster recovery operations. Cloud Backup allows you to efficiently manage the data on ECS instances. In addition, Cloud Backup allows you to protect data in advanced scenarios. For example, you can build test and development environments by using ECS instances, and you can perform geo-disaster recovery at low costs. For more information, see Overview and Back up ECS instances.
You can use the ECS instance backup feature to back up ECS instances, restore ECS instances, clone ECS instances, and clone disks.
Differences
ECS instance backup is implemented based on the snapshot service. ECS instance backup supports most of the capabilities and scenarios of the snapshot service. When you use the ECS instance backup feature, you can focus on the ECS instances that you want to back up. All ECS disks can be automatically discovered and tracked. You can flexibly restore and clone ECS instances and disks.
We recommend that you use the ECS instance backup feature of Cloud Backup if you need to perform local or remote backup or build and copy test and development environments based on ECS instances.
Item | Snapshot service | ECS instance backup |
Fee | For more information, see Snapshots. | |
Implementation method | The snapshot service is implemented based on the snapshot technology. For more information, see Overview and How snapshots work. | ECS instance backup is implemented based on the orchestration of snapshot service APIs, such as the APIs related to disk snapshots, snapshot-consistent groups, and snapshot remote replication. For more information, see the "Snapshots" section in API Reference. |
Protected object | Only the specified disks are protected. Local disks are not supported. | Specified ECS instances and disks can be protected. You can select multiple ECS instances and specify the disks of each ECS instance. Local disks are not supported. |
Backup by group | Only enhanced SSDs (ESSDs) can be backed up. | You can select all ECS disks. If all disks are ESSDs, Cloud Backup automatically creates a snapshot-consistent group. Otherwise, Cloud Backup creates snapshots only at a specific point in time to ensure the crash consistency of disks. |
Tracking of disks | None. | If you turn on Protect All Disks for an ECS instance, all disks deleted or added are automatically tracked. |
Restoration method | Disks or images. | You can roll back ECS instances, clone ECS instances across regions, restore disks, and clone disks. |
Management method | You can manage disk snapshots in table view. | You can manage the backup policies configured for source ECS instances, view the backup history, and restore and clone ECS instances. |
Snapshot visibility | In the ECS console, you can view all snapshots, including the disk snapshots created in Cloud Backup. | In the Cloud Backup console, you can view only the disk snapshots created in Cloud Backup. |
Number of snapshots per disk | A maximum of 256 manual snapshots and 1,000 auto snapshots can be created. For more information, see the "Snapshot limits" section in Limits. | A maximum of 256 snapshots can be created. For other items related to snapshots, the limits are the same for ECS instance backup and the snapshot service. For more information, see the "Snapshot limits" section in Limits. |
References
Cloud Backup provides resource plans for various backup scenarios so that you can enjoy higher discounts and minimize your costs. For more information, see Purchase resource plans.
Cloud Backup allows you to back up directories and files on ECS instances. You can view and restore data at any time. For more information, see Back up files from an ECS instance.
Cloud Backup allows you to migrate directories and files from on-premises servers to the cloud. You can view and restore data at any time. For more information, see Back up on-premises files.
For more information about Cloud Backup, see What is Cloud Backup?