A consistency check is a strategy used to harmonize data found in a computer system. The idea behind verification is to ensure that all data is in sync between the primary and secondary data pools, also known as protection groups and replicas. A consistency check can be configured to occur at designated times or manually implemented if there is any suspected data conflict since the last completed check.
man holding computer
Resolving internal conflicts is the main focus of a consistency check. Many systems include what is known as a data protection manager that analyzes the data in blocks, ensuring that the protection group and replica are in harmony. In the event that data updates occur with the protection group but not with the replica, the administrator adds the updates to the secondary data group, resolving the conflict.
The process of managing this type of verification varies slightly from system to system. Typically, a system administrator can set a recurring schedule to run the scan at least once every twenty-four hours. For example, verification can be set to occur just before midnight each day. You can also set scans to recur on specific days of the calendar month, or to run weekly or biweekly. Setting a schedule of permanent or recurring scans does not limit the administrator’s ability to perform random scans whenever and however desired.
The actual process of performing a consistency check can take some time. This is because the check does not simply look for exceptions, but actively compares each block of data between the two groups. This allows any corruption that may have occurred in one group or another to be identified and offers an opportunity to repair the damage. Some systems flag discrepancies, allowing a system administrator to review conflicting data before probabilities actually occur.
It is generally not recommended to attempt to reboot a system while a verification is in progress. This process may corrupt data or cause some other adverse effect, depending on your system configuration. If an emergency consistency check is initiated, it is generally a good idea for end users to refrain from attempting to use the system for any reason until the check is complete.
In addition to taking time to complete, this verification can also slow down other activities on the system. This means that end users may notice a change in how quickly they can access different databases or use any of the other programs connected to the system. For this reason, a computer consistency check is often set to run during off-peak hours, such as after work ends or at night when home computer users are asleep.
