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If the instance was booted from a volume and you want to store the root disk in the image repository, first you need to create volume from snapshot:

Via Horizon Dashboard

1. Go to Project → Compute → Volumes → Snapshots.
2. Find the snapshot and select Create Volume from the action menu.
3. Provide a name for the volume and confirm.

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openstack volume create --snapshot <snapshot_id> <volume_name>

Uploading a Volume to Glance as an Image

Via Horizon Dashboard

1. Navigate to Project → Compute → Volumes.
2. Locate the desired volume, and in the Actions column, select Upload to Image.
3. Provide an Image Name, choose a Disk Format, and click Upload.

Via CLI

openstack image create --volume <volume_id> <image_name>

Restoring an Instance from a Snapshot

Via Horizon Dashboard

• Navigate to Project → Compute → Instances.
• Click Launch Instance.
• In the Source tab, select Image and choose the desired snapshot.
• Complete the remaining fields (e.g., flavor, network) and click Launch Instance.

Via CLI

openstack server create --image <snapshot_id> --flavor <flavor_id> <new_instance_name>