In some cases, when you are about to clone an instance, it is necessary to preserve the data. There can be a myriad of reasons for you to clone your ServiceNow data to a new instance, and if the data is cloned without using Clone Data Preserver, you can experience serious problems, such as data loss or damage.
For example, if a MID Server is your target, then you must not overwrite that table. With Clone Data Preserver, you are able to store the preserved data on the target instance, even before cloning begins, and then restore it after cloning is completed.
What is the Clone Data Preserver?
ServiceNow is equipped with a feature called Clone Data Preserver, which enables users to define what data should and shouldn’t be replaced when cloning one environment into another. The Clone Data Preserver can preserve themes and settings, such as:
- User Preference [sys_user_preference]
- Bookmark [sys_ui_bookmark]
- Recent Selection [sys_ui_recent_selection]
- Instance-specific authentication settings
Why Should I Use It?
Before the clone, preserved data is stored on the target instance in a dynamically generated list. After the clone is complete, it is restored on the target instance. Users define data preservers on the source instance. Because they are primarily intended to preserve system settings, you should not attempt to use data preservers to transfer large volumes or sets of data (e.g., user groups). If you need to preserve large table data, such as roles, groups, and users, you should consider exporting these records to a file and importing it after cloning.
When cloning an environment, what you also clone is application integration. In that case, you lose the application configuration (e.g., AG or CI mappings, API keys, and service IDs) in the target environment. Utilizing the Clone Data Preserver is essential for cloning an integration and keeping it in a functional state.
Data Preservation Procedure
- Open your ServiceNow dashboard, navigate to System Clone > Preserve Data, and click New.
- After considering what data to preserve, enter the preservation table label as the Name of that instance. For example, name the table User Preference when preserving the [sys_user_preference] table.
- Select the Table you want to preserve.
- If the data being preserved is a UI property, tick the Theme checkbox.
- Use the Condition Builder to define the data to be preserved. Conditions can be used for defining specific records you want to preserve. For example, adding conditions for each property name that you want to preserve will help preserve only particular system properties.
- Click Submit. If you plan to delete the data preserver after cloning is complete, make sure you don’t delete or modify these data preserver records – Email Accounts, Semaphores, and Core Instance Properties.
During a cloning process, the target instance may be unavailable. In case users want to request a rollback of an instance to its pre-clone state, they have up to 24 hours to contact Customer Support.