Improved retry mechanism for backup validations

Detail name	Value
Changelog Number	12237
Type	Improvement
Status	Resolved
Fix Versions	Exasol 7.1.0, Exasol 6.2.15, Exasol 7.0.10
Resolution Date	2021-05-27

Description

The remote backup process of an Exasol database consists of multiple stages. For backups to a cloud storage (S3, Google Cloud Storage, Azure Blob Storage), the backup files are generally uploaded in chunks and after all data has been uploaded, the backup file is validated to verify the backup is consistent. 
If any step fails (e.g due to an intermittent error in the cloud storage), then the backup fails and must be restarted completely.

Improvement

If the validation step fails, the backup process now performs a retry of this step, which prevents having to re-run the entire backup again