When an instance no longer needs access to a volume, you can detach the volume from the instance without affecting the volume's data.
Required IAM Policy
To use Oracle Cloud Infrastructure, you must be given the required type of access in a policy written by an administrator, whether you're using the Console or the REST API with an SDK, CLI, or other tool. If you try to perform an action and get a message that you don’t have permission or are unauthorized, confirm with your administrator the type of access you've been granted and which compartment you should work in.
For administrators: The policy in Let users launch Compute instances includes the ability to attach/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 Getting Started with Policies 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.
Using the Console
For volumes attached using iSCSI, we recommend that you unmount and disconnect the volume from the instance using
iscsiadm before you detach the volume. Failure to do so may lead to loss of data. See Disconnecting From a Volume for more information.
- Open the navigation menu. Under Core Infrastructure, go to Compute and click Instances.
- In the Instance list locate the instance. Click its name to display the instance details.
- In the Resources section on the Instance Details page, click Attached Block Volumes
- Click Detach next to the volume you want to detach and confirm the selection when prompted.
Using the API
To delete an attachment, use the following operation:
For information about using the API and signing requests, see REST APIs and Security Credentials. For information about SDKs, see Software Development Kits and Command Line Interface.