There is no direct way to backup custom managed images. You can create a delete lock on the image. Please see this StackOverflow thread which provides some more information.
You can implement a full snapshot copy by doing the following,
- First, take a snapshot of the base blob using the Snapshot Blob operation.
- Then, copy the snapshot to a target storage account using Copy Blob.
- Repeat this process to maintain backup copies of your base blob.
For product feedback and feature requests I will refer you to our feedback forum. This allows the community to add their voice and upvote popular ideas. The forums are monitored and responded to by our product teams.
https://feedback.azure.com
Hope this helps! Let us know if you have further questions or issues and we will be happy to assist.
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