A storage operation accessing the Windows Azure Storage Service can fail in various ways. For example, there could be an unexpected timeout if the storage service is moving a partition for performance reasons. It is advisable, therefore, to code defensively in the assumption that failure could occur unexpectedly.
The Windows Azure Storage Client library supports defensive coding by providing a retry policy for operations to the storage service. This is done by default, but the retry policy classes support parameterization and customization of the process.
CloudBlobClient has a RetryPolicy property. A storage operation on a CloudBlob object has a retry policy associated with it through the RetryPolicy property of its BlobRequestOptions parameter. These RetryPolicy properties provide access to a RetryPolicy delegate that returns a ShouldRetry delegate which specifies whether or not a retry should be attempted.