Working with persistent disk snapshots

Create snapshots to periodically back up data from your zonal persistent disks or regional persistent disks.

You can create snapshots from disks even while they are attached to running instances. Snapshots are global resources, so you can use them to restore data to a new disk or instance within the same project. You can also share snapshots across projects.

Before you begin

• If you want to use the command-line examples in this guide:
  1. Install or update to the latest version of the gcloud command-line tool.
  2. Set a default region and zone.
• If you want to use the API examples in this guide, set up API access.

Creating snapshots

To prepare for creating persistent disk snapshots, do the following:

• Review Best practices for persistent disk snapshots to prepare your disk for snapshotting.

• Read Creating a persistent disk snapshot schedule to learn about creating a snapshot schedule and attaching it to your disks. Backing up your disks regularly with scheduled snapshots can reduce the risk of unexpected data loss.

Creating a snapshot of a zonal persistent disk

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.snapshots.create on the project
• compute.instances.useReadOnly on the source instance
• compute.disks.createSnapshot on the disk

Console

1. Go to the Create a Snapshot page in the Google Cloud Console.
   Go to the Create a Snapshot page
2. Enter a snapshot Name.
3. Optionally, enter a Description of the snapshot.
4. Select the Source disk from the drop-down menu.

5. Determine your snapshot storage location. You can use the default storage location, or a custom storage location.

   1. Under Location, select whether you want to store your snapshot in a Multi-regional location or a Regional location.
   2. Select which specific region or multi-region that you want to use. To use the region or multi-region that is closest to your source disk, select Based on disk's location (default).

6. Click Create to create the snapshot.

gcloud

Create your snapshot in the default storage location or in a selected storage location. Optionally, you can specify a snapshot name with the --snapshot-names flag. The default snapshot name is a random 12-character alphanumeric string that starts with a letter.

• To create a snapshot of a zonal persistent disk in the default storage location, use the gcloud compute disks snapshot command:

  gcloud compute disks snapshot DISK_NAME
  

  where:

  • DISK_NAME is the name of the zonal persistent disk from which you want to create a snapshot.

• Alternatively, to create a snapshot in a custom storage location, use the --storage-location flag to indicate where to store your snapshot:

  gcloud compute disks snapshot DISK_NAME \
      --storage-location STORAGE_LOCATION
  

  where:

  • DISK_NAME is the name of the zonal persistent disk from which you want to create a snapshot.
  • STORAGE_LOCATION is the Cloud Storage multi-region or the Cloud Storage region where you want to store your snapshot. You can specify only one storage location.

The gcloud tool waits until the operation returns a status of READY or FAILED, or reaches the maximum timeout and returns the last known details of the snapshot.

API

Create your snapshot in the default storage location or in a selected storage location. Optionally, you can specify a snapshot name with the name field. The default snapshot name is a random 12-character alphanumeric string that starts with a letter.

• To create your snapshot in the default storage location, make a POST request to the disks.createSnapshot method:

  POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/zones/ZONE/disks/DISK_NAME/createSnapshot
  

  where:

  • PROJECT_ID is your project ID.
  • ZONE is the zone where your instance and disk are located.
  • DISK_NAME is the name of the zonal persistent disk from which you want to create a snapshot.

• Alternatively, to create a snapshot in a custom storage location, make a POST request to the disks.createSnapshot method and specify the storage location:

  POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/zones/ZONE/disks/DISK_NAME/createSnapshot
  
  {
    "storageLocations": STORAGE_LOCATION
  }
  

  where:

  • PROJECT_ID is your project ID.
  • ZONE is the zone where your instance and disk are located.
  • DISK_NAME is the name of the zonal persistent disk from which you want to create a snapshot.
  • STORAGE_LOCATION is the Cloud Storage multi-region or the Cloud Storage region where you want to store your snapshot. You can specify only one storage location.

Caution: If you attempt to create a snapshot from a zonal persistent disk and the snapshotting process fails, you won't be able to delete the original zonal persistent disk until you have cleaned up the failed snapshot. This failsafe helps to prevent the accidental deletion of source data in the event of an unsuccessful backup.

Creating a snapshot of a regional persistent disk

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.snapshots.create on the project
• compute.instances.useReadOnly on the source instance
• compute.disks.createSnapshot on the disk

After you have prepared the disk, you can create a snapshot. When creating a snapshot of a regional persistent disk, you must indicate the region where the disk is located.

Console

1. Go to the Create a Snapshot page in the Google Cloud Console.
   Go to the Create a Snapshot page
2. Enter a snapshot Name.
3. Optionally, enter a Description of the snapshot.
4. Under Source disk, select an existing disk from which you want to create a snapshot.

5. Optionally, you can specify a custom storage location:

   1. Under Location, select whether you want to store your snapshot in a Multi-regional location or a Regional location.
   2. Select which specific region or multi-region that you want to use. To use the region or multi-region that is closest to your source disk, select Based on disk's location.

6. Click Create to create the snapshot.

gcloud

Create your snapshot in the default storage location or in a selected storage location.

• To create a snapshot of a regional persistent disk in the default storage location, use the gcloud compute disks snapshot command.

  gcloud compute disks snapshot DISK_NAME \
      --region REGION
  

  where:

  • DISK_NAME is the name of the regional persistent disk from which you want to create a snapshot.
  • REGION is the region where your regional persistent disk is located.

• Optionally, you can specify a custom storage location:

  gcloud compute disks snapshot DISK_NAME --region
      REGION --storage-location STORAGE_LOCATION
  

  where:

  • DISK_NAME is the name of the regional persistent disk from which you want to create a snapshot.
  • REGION is the region where your regional persistent disk is located.
  • STORAGE_LOCATION is the Cloud Storage multi-region or the Cloud Storage region where you want to store your snapshot. You can specify only one storage location.

  The gcloud command-line tool waits until the operation returns a status of READY, FAILED, or reaches the maximum timeout and returns the last known details of the snapshot.

API

• To create a snapshot in the default storage location, make a POST request to the regionDisk.createSnapshot method:

  POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/regions/REGION/disks/DISK_NAME/createSnapshot
  

  where:

  • PROJECT_ID is your project ID.
  • REGION is the region where your regional persistent disk is located.
  • DISK_NAME is the name of the disk you want to snapshot.

• Alternatively, to create a snapshot in a custom storage location, make a POST request to the regionDisk.createSnapshot method and specify the storage location:

  POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/regions/VAR/disks/DISK_NAME/createSnapshot
  {
   "storageLocations": STORAGE_LOCATION
  }
  

  where:

  • PROJECT_ID is your project ID.
  • REGION is the region where your regional persistent disk is located.
  • DISK_NAME is the name of the regional persistent disk from which you want to create a snapshot.
  • STORAGE_LOCATION is the Cloud Storage multi-region or the Cloud Storage region where you want to store your snapshot. You can specify only one storage location.

Caution: If you attempt to create a snapshot from a regional persistent disk and the snapshotting process fails, you won't be able to delete the original regional persistent disk until you capture a clean snapshot. This failsafe prevents the accidental deletion of source data in the event of an unsuccessful backup.

Sharing snapshots across projects

To move disk data across projects, share a snapshot of the disk with users in other projects. For example, to move the data from the disk disk-1 in project-a to a new disk disk-2 in project-b, use the following steps. In this example, disk-1 is located in zone us-west2-a and instance-1 is located in zone us-west2-b.

gcloud

1. Create a snapshot of disk-1:

   gcloud compute disks snapshot disk-1 --project project-a --snapshot-names snapshot-1
   

2. Create a new disk in project-b that is based on the snapshot:

   gcloud compute disks create disk-2  --project project-b --source-snapshot projects/project-a/global/snapshots/snapshot-1
   

3. Attach the new disk to the instance instance-1 in project-b.

   gcloud compute instances attach-disk instance-1 --project project-b --disk disk-2
   

   Note: The disk must be in the same zone as the instance.

4. Mount the disk. See steps 5-7 of Formatting and mounting a persistent disk.

API

1. Create a snapshot of disk-1 by making a POST request to the disks.createSnapshot method.

   POST https://compute.googleapis.com/compute/v1/projects/project-a/zones/us-west2-a/disks/disk-1/createSnapshot
   
   {
   "name": "snapshot-1"
   }
   

2. Create a new disk disk-2 in project-b that is based on the snapshot. Construct a POST request to create a zonal persistent disk using the disks.insert method.

   POST https://compute.googleapis.com/compute/v1/projects/project-b/zones/us-west2-b/disks
   
   {
   "name": "disk-2",
   "type": "zones/us-west2-b/diskTypes/DISK_TYPE"
   "sourceSnapshot": "projects/project-a/global/snapshots/snapshot-1"
   }
   

   Replace the following:

   • DISK_TYPE: The type of persistent disk. Either pd-standard, pd-ssd, or pd-balanced.

3. Attach the new disk to the instance instance-1 in project-b. The disk must be in the same zone as the instance. Construct a POST request to the instances.attachDisk method, and include the URL to the zonal persistent disk that you just created.

   POST https://compute.googleapis.com/compute/v1/projects/project-b/zones/us-west2-b/instances/instance-1/attachDisk
   
   {
   "source": "/compute/v1/projects/project-b/zones/us-west2-b/disks/disk-2"
   }
   

4. Mount the disk. See steps 5-7 of Formatting and mounting a persistent disk.

To get a list of snapshots available to you, see Listing snapshots.

Restoring snapshots

To restore the contents of a snapshot to a new disk, you have the following options:

• Create a new persistent disk from a snapshot: Create a new disk and select the snapshot as the Source.

• Create a new instance from a snapshot: When you create a new instance, you can use snapshots to create boot disks and data disks for that instance. In the event of an outage, you can quickly recover your data by restoring one or more snapshots to the new persistent disks on a new instance. For more information, see Creating an instance from snapshots.

Creating a new persistent disk from a snapshot

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.disks.create on the project to create a new disk
• compute.instances.attachDisk on the VM instance
• compute.disks.use permission on the disk to attach

The new persistent disk must be at least the same size as the original source disk for the snapshot. If you create a persistent disk that is larger than the original source disk for the snapshot, you must resize the file system on that persistent disk to include the additional disk space.

You can create a new zonal persistent disk from a given snapshot at most once every ten minutes. If you want to issue a burst of requests to snapshot your disks, you can issue at most 6 requests in 60 minutes. This limit does not apply when creating regional persistent disks from a snapshot. For more information, see Snapshot frequency limits.

Depending on your operating system and file system type, you might need to use a different file system resizing tool. For more information, see your operating system documentation.

Console

1. In the Google Cloud Console, go to the Snapshots page.

   Go to Snapshots

2. Find the name of the snapshot that you want to restore.

3. Go to the Disks page.

   Go to the Disks page

4. Click Create new disk.

5. Specify the following configuration parameters:

   • A name for the disk.
   • A type for the disk.
   • Optionally, you can override the default region and zone selection. You can select any region and zone, regardless of the storage location of the source snapshot.

6. Under Source type, click Snapshot.

7. Select the name of the snapshot to restore.

8. Optional: Select a size in gigabytes, for the disk. This number must be equal to or larger than the original source disk for the snapshot. If you do not specify this value, the new disk is the same size as the original source disk for the snapshot.

9. Click Create to create the disk.

gcloud

1. Use the gcloud compute snapshots list command command to find the name of the snapshot you want to restore:

   gcloud compute snapshots list
   

2. Use the gcloud compute snapshots describe command command to find the size of the snapshot you want to restore:

   gcloud compute snapshots describe SNAPSHOT_NAME
   

   Replace SNAPSHOT_NAME with the name of the snapshot being restored.

3. Use the gcloud compute disks create command command to create a new regional or zonal persistent disk from your snapshot. If you need an SSD persistent disk for additional throughput or IOPS, include the --type flag and specify pd-ssd.

   gcloud compute disks create DISK_NAME \
       --size=DISK_SIZE \
       --source-snapshot=SNAPSHOT_NAME \
       --type=DISK_TYPE
   

   Replace the following:

   • DISK_NAME: the name of the new disk.
   • DISK_SIZE: the size, in gigabytes, of the new disk. This number must be equal to or larger than the original source disk for the snapshot.
   • SNAPSHOT_NAME: the name of the snapshot being restored.
   • DISK_TYPE: the type of the persistent disk. For example, pd-ssd.

API

1. Construct a GET request to snapshots.list to display the list of snapshots in your project.

   GET https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/global/snapshots
   

   Replace PROJECT_ID with your project ID.

2. Construct a POST request to create a zonal persistent disk using the disks.insert method. Include the name, sizeGb, and type properties. To restore a disk using a snapshot, you must include the sourceSnapshot property.

   POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/zones/ZONE/disks
   
   {
    "name": "DISK_NAME",
    "sizeGb": "DISK_SIZE",
    "type": "zones/ZONE/diskTypes/DISK_TYPE"
    "sourceSnapshot": "SNAPSHOT_NAME"
   }
   

   Replace the following:

   • PROJECT_ID: your project ID.
   • ZONE the zone where your instance and new disk are located.
   • DISK_NAME: the name of the new disk.
   • DISK_SIZE: the size, in gigabytes, of the new disk.
   • DISK_TYPE: the type of the persistent disk. For example, pd-ssd.
   • SNAPSHOT_NAME: the source snapshot for the disk you are restoring.

Optionally, you can then attach the new disk to an existing instance.

Console

1. Go to the VM instances page.

   Go to the VM instances page

2. Click the name of the instance where you want to restore your non-boot disk.
3. At the top of the instance details page, click Edit.
4. Under Additional disks, click Attach existing disk.
5. Select the name of the new disk made from your snapshot.
6. Click Done to attach the disk.
7. At the bottom of the instance details page, click Save to apply your changes to the instance.

gcloud

1. Use the gcloud compute instances attach-disk command to attach your persistent disk to an instance:

   gcloud compute instances attach-disk INSTANCE_NAME \
       --disk DISK_NAME
   

   where:

   • INSTANCE_NAME is the name of the instance.
   • DISK_NAME is the name of the disk made from your snapshot.

API

1. Construct a POST request to the instances.attachDisk method, and include the URL to the zonal persistent disk that you just created from your snapshot.

   POST https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/zones/ZONE/instances/INSTANCE_NAME/attachDisk
   
   {
    "source": "/compute/v1/projects/PROJECT_ID/zones/ZONE/disks/DISK_NAME"
   }
   

   where:

   • PROJECT_ID is your project ID.
   • ZONE is the zone where your instance and new disk are located.
   • INSTANCE_NAME is the name of the instance where you are adding the new persistent disk.
   • DISK_NAME is the name of the new disk.

After you create and attach a new disk to an instance, you must mount the disk so that the operating system can use the available storage space.

Important: If you create a VM instance from a disk snapshot based on a Shielded VM image, the original integrity policy baseline is lost and the first set of boot sequence measurements on the new VM instance is used as the new baseline. Because this new set of measurements is not verified, validate the VM instance's boot integrity after restoring from a snapshot. You can do this by manually examining the boot log and verifying that the proper keys are loaded into the SecureBoot database, and that the expected kernel version is running. Also, secrets saved in the vTPM on the originating VM instance are not accessible on VM instances restored from a snapshot of that instance.

Deleting a snapshot

Compute Engine uses incremental snapshots so that each snapshot contains only the data that has changed since the previous snapshot. Because subsequent snapshots might require information stored in a previous snapshot, keep in mind that deleting a snapshot does not necessarily delete all the data on the snapshot. To learn more about snapshot deletion, see Snapshot deletion.

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.snapshots.delete on the snapshot

To delete a snapshot:

Console

1. Go to the Snapshots page in the Google Cloud Console.

   Go to the Snapshots page

2. Select one or more snapshots that you want to delete.
3. At the top of the Snapshots page, click Delete.

gcloud

To delete a snapshot, use the gcloud compute snapshots delete command:

gcloud compute snapshots delete SNAPSHOT_NAME

where SNAPSHOT_NAME is the name of the snapshot being deleted.

API

Make a DELETE request to compute.snapshots.delete method to delete snapshots.

DELETE https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/global/snapshots/SNAPSHOT_NAME

where:

• PROJECT_ID is the name of your project.
• SNAPSHOT_NAME is the name of the snapshot to delete.

Listing snapshots

Permissions required for this task

To perform this task, you must have the following permissions:

• compute.snapshots.list on the project

gcloud

To see a list of snapshots available to you in a particular project, use the gcloud compute snapshots list command.

gcloud compute snapshots list --project PROJECT_ID

where PROJECT_ID is the ID of the project.

API

To see a list of snapshot available to you in a particular project, make a GET request to the snapshots.list method:

GET https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/global/snapshots

where PROJECT_ID is the ID of the project.

Viewing information about a snapshot

To list information about a particular snapshot, such as the creation time, size, and source disk, use the gcloud compute snapshots describe command:

gcloud compute snapshots describe SNAPSHOT_NAME

where SNAPSHOT_NAME is the name of the snapshot.

What's next

• Learn how to create a snapshot schedule for persistent disks.
• Learn how to create a disk image from your snapshot.