[Yandex Cloud documentation](../../index.md) > [Yandex Cloud Backup](../index.md) > Concepts > Overview

# Yandex Cloud Backup overview


Yandex Cloud Backup is a service for creating backups and restoring Yandex Cloud resources and their data. Backup and recovery are available for [Compute Cloud VMs](../../compute/concepts/vm.md) created from [supported Cloud Marketplace images](vm-connection.md#os) as well as for [Yandex BareMetal servers](../../baremetal/concepts/servers.md) with [supported operating systems](vm-connection.md#self-install).

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You can restore neither a VM backup to a BareMetal server, nor a BareMetal server backup to a VM.

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VM and BareMetal server backups are application-consistent: they save not only the data on disks but also the data already submitted but not yet fully written to the disk. This allows you to resume applications that were running at the time of the backup directly after recovering a VM or BareMetal server from the backup. This is important for VMs and servers forming a part of data storage systems, such as when a DBMS is running on the VM or BareMetal server.

Cloud Backup can create [full and incremental backups](backup.md#types). A full backup stores the whole of the VM or BareMetal server data: the recovery is faster than from an incremental backup, yet such backups take up more storage space and take longer to be created. An incremental backup only stores data that is different from the previous backup. It is faster to create and takes up less space. However, recovery from an incremental backup takes longer than from a full one. If you know your VM or BareMetal server has changed a lot since the previous backup, it is better to make a full backup.

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If you use a policy with the `fastBackupEnabled` [option](policy.md#specification) and ran an antivirus scan before creating an [incremental backup](backup.md#types), the backup time may increase significantly. Read more in [Interaction with an antivirus](av-interaction.md).

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With Cloud Backup, you can also restore individual files and directories from a backup to any VM connected to the service. For more information, see [File-by-file recovery](backup.md#file-by-file). File-by-file recovery to BareMetal servers is currently not available.

To enable backups for a VM or BareMetal server, you first need to have it connected and configured. For more information, see [Connecting Compute Cloud VMs and Yandex BareMetal servers to Cloud Backup](vm-connection.md).

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When initiating a backup, make sure the VM or BareMetal server is running.

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Once you have connected your VM or BareMetal server to Cloud Backup and configured it, you need to link it to a [backup policy](policy.md), i.e., a Cloud Backup resource. The policy includes settings for creating and storing backups. You can link your VMs and BareMetal servers to default policies or create custom policies.

Cloud Backup automatically delivers [metrics](../metrics.md) on the number of protected VMs and BareMetal servers, as well as storage space used by backups, to [Yandex Monitoring](../../monitoring/index.md).

The service has two types of restrictions: [quotas and limits](limits.md).

## Comparison with VM disk snapshots in Compute Cloud {#snapshot-comparison}

| | Disk snapshots in Compute Cloud | Cloud Backup |
| --- | --- | --- |
| **Granularity** | Disk | VMs with all disks<br>Individual files and folders<br>VM applications (coming soon). |
| **Disk types** | All types except local disks on [dedicated hosts](../../compute/concepts/dedicated-host.md).<br>The snapshot creation time is not fixed for [non-replicated disks and SSD-IO](../../compute/concepts/disk.md#nr-disks). | All disk types |
| [**LVM**](backup.md#lvm) | Not supported | Supported |
| **Recovery** | Full recovery to a new VM only. | To a new or existing VM.<br>Partial recovery of individual files. |
| **Consistency** | Atomic snapshot of each disk. | Atomic snapshot of the entire VM, individual folders, or files. |
| **Backup integrity checks** | Not supported | Supported |
| **Agent installation** | Not required | Required, installed automatically when connecting a VM to the service. |
| **Optimization** | Full backups only.<br>Data compression is not supported. | Full or incremental backups.<br>Multiple data compression levels with an option to opt out. |
| **Pricing** | Per GB of stored backups. | Per GB of stored backups and VM connection fee. |
| **Required VM status** | You can create a [snapshot](../../compute/concepts/snapshot.md) on both stopped or running VMs. | You can only create a snapshot on a running VM with the [Cloud Backup agent](agent.md) installed. |

## Service activation and backup provider {#providers}

Cloud Backup is enabled by a _backup provider_. Currently, the service only has one provider available: Cyberprotect.

For correct operation, the [Cloud Backup agent](agent.md) installed on a VM or BareMetal server sends configuration service metadata to the provider's servers:

* VM or BareMetal server name.
* OS name and version.
* OS core version.
* VM or BareMetal server internal IP address.
* MAC address of each BareMetal server network adapter or VM network interface.
* Amount of RAM.
* CPU model and frequency.
* CPU type, physical or virtual.
* Type of virtualization: hardware or software VM virtualization.
* Names of mount points and [disks](../../compute/concepts/disk.md) connected to the VM or BareMetal server.

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The data stored on the user's Compute Cloud VMs or BareMetal servers, same as its backups, never leave Yandex Cloud.

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To get started, you need to activate the service, i.e., to connect to a backup provider. You can [activate](../operations/activate-service.md) the service directly or [connect](vm-connection.md) your first VM or BareMetal server to Cloud Backup, which activates the service automatically.

To activate the service, you need _at least_ the `backup.user` [role](../security/index.md#backup-user) for the [folder](../../resource-manager/concepts/resources-hierarchy.md#folder) in which you want to create backups of VMs or BareMetal servers.

After activation, the system automatically creates the following backup policies:
* `Default daily`: Daily incremental backup with the last 15 backups retained.
* `Default weekly`: Weekly incremental backup with the last 15 backups retained.
* `Default monthly`: Monthly incremental backup with the last 15 backups retained.


## Use cases {#examples}

* [Connecting a Yandex BareMetal server to Cloud Backup](../tutorials/backup-baremetal.md)
* [Associating a Yandex Cloud Backup policy to a VM automatically](../tutorials/vm-with-backup-policy/index.md)