OpenStack Cinder Metadata: attached-mode and readonly
When you attach a volume to an instance, Cinder automatically adds the
key-value pairs to the volume. These tags describe the state of the volume and are not directly modifiable by the user.
attached_mode key describes whether the volume is read-only or read-writable and appears only when the volume is attached.
readonly key describes whether the volume can be attached as read-only or read-writeable .
Cinder automatically removes the
attached_mode key when the volume is detached from an instance. However, the
readonly key stays indefinitely.
To attach a volume as read-only, set the read-only mode to
true using the Cinder client:
cinder readonly-mode-update true
To attach as volume as read-writeable, set the read-only mode to
cinder readonly-mode-update false