Sample : http://code.msdn.microsoft.com/How-to-create-a-snapshot-f6558876
This Code Snippet shows how to create a snapshot of blob in Windows Azure.
For developers, the best way to prevent accidental deletion or modification is creating a snapshot of blob.A snapshot is a read-only version of a blob that's taken at a point in time. Once a snapshot has been created, it can be read, copied, or deleted, but not modified. Snapshots provide a way to back up a blob as it appears at a moment in time. A snapshot of a blob has the same name as the base blob from which the snapshot is taken, with a DateTime value appended to indicate the time at which the snapshot was taken. A blob may have any number of snapshots. Snapshots persist until they are explicitly deleted. A snapshot cannot outlive its source blob. You can enumerate the snapshots associated with your blob to track your current snapshots.
This script can help developers easily create a snapshot of a specific blob storage.
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