Backup Verification and Validation: Use Self Validating Backups

BackupChain®: Backup Software and Toolset Made for IT Professionals

BackupChain backup software is an all-in-one solution for Windows Servers and PCs and contains sophisticated backup verification and backup validation tools to ensure that your backups are functional long before you will need to restore. BackupChain’s backup verification features protect against many causes of backup data loss, such as bit rot, employee vandalism, malware, ransomware, RAM defects, and even partial disk defects that typically go unnoticed.

Why Bother Verifying and Validating the Backup Process and Backup Data?

Many professionals who haven’t experienced total data loss assume that digital storage is perfect and digital devices are always functioning perfectly; however, the reality is very different. Storage is becoming more and more dense and one hard drive holds more information than ever before. At the same time, the error rate isn’t going down dramatically, so the probability of a failure per device actually increased in recent years. In addition, other threats of data loss have become more common. Ransomware, malware, and vandalism caused by disgruntled employees, for example, are external causes of data loss, while bit rot, disk defects, and RAM defects affect the device itself.
Another trend in recent years is to utilize incremental backup schemes to speed up the backup process. Unfortunately, what many professionals don’t realize is that incremental backups introduce a dependency to the previous backup. If any backup in the chain of backups becomes corrupt, for whatever reason, the entire chain or at least parts of the backup chain become unreadable. The real reason why incremental scheme became popular is that despite the advances in storage volume, hard drive manufacturers couldn’t increase the throughput speeds at the same pace, using the same technology. SSD storage has a much better throughput rate but unfortunately also a much higher error rate, as well as a much faster wear-and-tear. Cells inside SSD drives wear out fast and are being replaced by spare cells inside the drive itself automatically. However, the “soon-to-fail-cell” detection process is usually deferred until the cell is actually being read, which typically won’t occur often with backup drives.

Backup Verification

BackupChain offers backup options to verify backup files immediately upon completion. These functions bypass the Windows caching system to ensure the data file is actually being read back from the disk it was stored. Unique to BackupChain is its ability to do the same for remote storage as well. The data is downloaded again to ensure each file was processed correctly. Additional options exist to limit this step to files of up to a certain size.

Backup Validation

Unique backup validation features in BackupChain allow users to validate files long after they were processed. Consider the following scenario: a typical small-business file server contains several terabytes of files and folders, typically about 10 million files or more. Typically less than 1% of these files are being changed over time, especially after a month or so after the final edit. On average, these files will remain at rest for years without being ever accessed. Bit rot, disk defects, malware, and simple deletions or file alterations caused by a disgruntled employee may go unnoticed until years later when the file server disks fail completely and a full restore is necessary. How can such a large dataset be validated efficiently?
BackupChain offers a unique solution to this problem, where terabytes of data are being backed up daily. BackupChain uses a validation feature that allows a random validation of a percentage of backup files at each backup cycle. You could, for example, configure BackupChain to only validate 1% of all your file server backup files. If your file server currently holds 1 million files, that would be 10,000 files to validate. By validating a random selection of 1% of all backup files, it would take 100 cycles on average to validate every file. If the backup runs 10 times a day, it would take 10 days to validate the entire backup set.
While small backup sets can be backed up and validated in full within hours, when you have to deal with millions of folders and dozens of terabytes of storage, it is no longer possible to validate the entire set at every backup cycle, due to limited data throughput speeds of the network connection and that of mechanical hard drives. As a compromise, BackupChain’s features cover the entire backup device by selecting a random subset at each backup cycle.
Re-reading backup files is critical because it refreshes all cells and sectors on the drive. By using BackupChain’s backup validation tool, your data will be ‘actualized’ by the drive, meaning the drive is forced to re-check the sector and do internal repairs as needed. If repairs are no longer possible, the drive will send a signal to Windows and BackupChain will log the problem and send alerts to inform you of the issue. In addition, BackupChain uses checksums and/or performs a 1:1 comparison with the original file to validate the contents of each backup file. Hence, backup validation is critical “insurance” to have: you have repeated proof that all files in your backup storage are in fact still valid and readable. If the validation mechanism finds an issue with the drive, you can take immediate action and replace the backup drive, long before a critical restore operation is needed.

What About Verifying a Disk Image or Disk Clone?

Apart from file-level backup, BackupChain also offers live disk cloning and disk imaging features. While both features work at the disk sector level, they also include an option to validate the file system at the file level, which is unique to BackupChain. The problem with other solutions is that they process the disk image at the sector-level and then also offer to verify it at the sector-level. Sector-level disk backups bypass the file system and read blocks directly from the disk drive. This is very efficient and much faster than file-by-file processing; however, if there are issues with the file system, they will go unnoticed. For example, each file system uses a bitmap to track free blocks. Sometimes it may be damaged and the disk imaging tool may erroneously skip over allocated blocks. Even the block-by-block verification won’t spot this issue because the same blocks are being read back. In order to catch this kind of file system error, each file needs to be read back from the disk image or disk clone created to ensure no critical sector was omitted, whatever the cause may be.

Download BackupChain Today

Download BackupChain today and use the fully functional 20 day trial to see the backup verification and validation process in action. Apart from file server backup, BackupChain offers a wide range of backup features, such as: Virtual Machine Backup, VMware Backup, Hyper-V Backup, VirtualBox backup, and Windows Server Backup.