Mirroring storage is mainly for migrating data from 3rd party storage/origin to CDNetworks Object Storage.

After setting it, when there is a new request to object storage, if object storage doesn’t have this object, our storage will do following actions:
1, Respond 302 to requester, and redirect to target origin;
2, Go to target origin and download file to object storage directly.

Go to Basic Setting -> Back-To-Origin, then click “edit”.