Oracle Cloud Infrastructure Documentation

Detaching a Boot Volume

If a boot volume issue is causing a compute instance issues, you can stop the instance and detach the boot volume, then attach it to another instance as a data volume to troubleshoot it.

Required IAM Policy

To use Oracle Cloud Infrastructure, an administrator must be a member of a group granted security access in a policy  by a tenancy administrator. This access is required whether you're using the Console or the REST API with an SDK, CLI, or other tool. If you get a message that you don't have permission or are unauthorized, verify with the tenancy administrator what type of access you have and which compartment  your access works in.

For administrators: The policy in Let users launch compute instances includes the ability to attach and detach existing block volumes. The policy in Let volume admins manage block volumes, backups, and volume groups lets the specified group do everything with block volumes and backups, but not launch instances.

If you're new to policies, see Managing Identity Domains and Common Policies. For reference material about writing policies for instances, cloud networks, or other Core Services API resources, see Details for the Core Services.

  • You can detach a boot volume from an instance only when the instance is stopped. See Stopping, Starting, or Restarting an Instance for information about managing an instance's state.

    1. Open the navigation menu  and select Compute. Under Compute, select Instances.

    2. Choose your Compartment.

    3. Select the instance that you want to detach the boot volume from.
    4. Under Resources, select Boot Volume.
    5. Select the Actions menu (three dots) for the boot volume, and then select Detach Boot Volume. Confirm when prompted.

    You can now attach the boot volume to another instance. For more information, see Attaching a Boot Volume.

  • Use the oci compute boot-volume-attachment detachcommand and specify the --boot-volume-id parameter to attach the volume to the instance:

    oci compute boot-volume-attachment detach --boot-volume-id boot_volume_id

    For a complete list of parameters and values for CLI commands, see the CLI Command Reference.

  • Run the DetachBootVolume operation and specify the bootVolumeAttachmentId attribute to detach a boot volume.