Data backup is essential to business or organization and having a data backup plan is only as good as the integrity of the backup data. To ensure that this objective is met, AhsayCBS backup server and AhsayOBM/AhsayACB client provides an improved Data Integrity Check (DIC) feature where the end user can easily verify the integrity of the data stored on the backup destination(s) (i.e. AhsayCBS, Cloud storage, or Local storage) to ensure that the backup data is recoverable.
In backing up large or even small file(s), data corruption may still occur during a backup job or even in a post-backup job. Some of the possible causes are:
Since data corruption is always a possibility, the solution is to identify and then remove corrupted files from the backup destination(s). Identifying and removing corrupted files from the backup destination(s) is mission critical as it measures the integrity of the backup data and its restorability.
The primary role of the Data Integrity Check is to identify and remove corrupted files from the backup destination(s). This will allow the next backup job to have an opportunity to back up these files again. However, corrupted files which are located in the retention area will not be backed up as the source file(s) no longer exists.
Data integrity check CANNOT fix or repair files that are already broken.
Data Integrity Check can be started using the following options:
There are two (2) data integrity check modes:
This is the default setting of the data integrity check. Running a data integrity check on this mode allows the AhsayOBM/AhsayACB client or AhsayCBS backup server to perform a comparison between the files and/or folders on the backup destination(s) and the list of the files and/or folders recorded in the current index file.
When should I run a Data Integrity Check in default mode?
Running a data integrity check on this mode will perform check on the integrity of the files in the backup destination(s) against the checksum file generated at the time of the backup job.
If there is a discrepancy, this indicates that the file(s) on the backup destination(s) are corrupted. The AhsayOBM/AhsayACB client or AhsayCBS backup server will remove these files from the backup destination(s). If these files still exist on the client machine or backup server on the next backup job, The AhsayOBM/AhsayACB client or AhsayCBS backup server will upload the latest copy.
For large file sizes, a percentage progress will be displayed throughout the data integrity check job when this setting is enabled:
When should I run a Data Integrity Check with Run Cyclic Redundancy Check (CRC) enabled?
With Periodic Data Integrity Check (PDIC) and post-backup validation features on the AhsayOBM/AhsayACB v188.8.131.52 or above, it is not necessary to frequently run a Data Integrity Check with Run Cyclic Redundancy Check (CRC) enabled. Also, this option can take a long time to complete as the AhsayOBM/AhsayACB will need to download all the files and/or folders from the backup destination(s) on the AhsayOBM/AhsayACB client machine in order to perform the actual Cyclic Redundancy Check (CRC).
To reduce the time taken, you should consider selecting only one backup destination at a time if applicable.
It is recommended to use this option:
If the AhsayOBM/AhsayACB client machine is accessing the internet on a metered internet connection plan, it will incur additional data charges from your ISP (Internet Service Provider) as a result of the data download.
If the backup destination(s) are commercial Cloud Storage destinations, it may incur additional charges from your Cloud Storage Provider as a result of the data download.
The following diagrams show the detailed flow for each data integrity check mode.
Normally aspart of the data integrityjob, (TEST MODE) confirmation screen is usually displayed once a data integrity check is completed, which gives a summary report of the corrupted files, invalid indexes,or storage statistics issue for each backup destination. The (TEST MODE) confirmation screen allows the enduser to review the results of the data integrity check, and to decide whether they would like to proceed with the corrective actions.To further streamline the data integrity check process and improve user experience,the (TEST MODE) confirmation screen will ONLY prompt if either of the criteria’s below matches the backup data during the data integrity check operation:
Otherwise, the data integrity check job will automatically take corrective actions.
The (TEST MODE) screen includes five (5) summary report for the following items found per backup destination:
|Destination||this indicates the destination of the backup data where the data integrity check will be run|
|Items found in index||the number of files and its total size (MB) that appear in the index|
|Data corrupted items||the number of files and its total size (MB) found to be corrupted|
|Index broken data blocks||index with its associated data blocks which found to be corrupted|
|Statistics||storage statistics status of the data area and retention area of the backup destination (i.e. correct or incorrect status)|
Although you select ALL backup sets before starting the data integrity check, the (TEST MODE) confirmation screen will prompt one at a time with the corresponding backup set(s).
For example, the data integrity check has run with three (3) backup sets and all these backup sets match the criteria’s of the (TEST MODE) confirmation screen, the (TEST MODE) confirmation screen will prompt three times to confirm if the end user will take corrective actions for the three backup sets.
Below is an example of a (TEST MODE) confirmation screen with the following scenario:
Periodic data integrity check is performed at the beginning of a backup job, which provides an additional regular data integrity check of the backup data and updates the storage statistics for each backup set. The PDIC feature is enabled from v184.108.40.206 or above and cannot be turned off. This is to ensure a maximum protection of the backup data.
Unlike with the Data Integrity Check (DIC), the PDIC starts automatically and performs a quick check of all the backup destination(s) without the end user intervention.
The PDIC will be initiated automatically once EITHER of the following conditions is met:
E.g. If the last PDIC job was run more than seven (7) days ago, then the subsequent PDIC job(s) will run seven days from that day onwards.
|Features||Data Integrity Check (DIC)||Periodic Data Integrity Check (PDIC)|
|Allows selection of backup destination(s)||✓||X|
|Run Cyclic Redundancy Check (CRC) feature||✓||X|
|Identify and remove the files and/or folders in the backup destination(s) which do not appear in the index||✓||✓|
|Identify and remove the files and/or folders which appear in the index but do not exist in the backup destination(s)||✓||X|
|Identify and remove partially uploaded (orphan) files from the backup destination(s)||✓||X|
|(TEST MODE) confirmation screen feature||✓||X|
|Update Storage Statistics||✓||✓|