Clone BasicsThis article answers the basic questions that ServiceNow Technical Support receive in relation to clones from a source instance to a target instance. Find out more about: how a clone works, clone roll back, cloning options, data server configuration, and cloning over a production instance. The source instance provides progress and automation milestone updates within its clone history record. If email notifications are desired for any of the milestone updates, the instructions in KB0966447 - Email notifications for clone can guide to create custom notifications in the source instance itself. This article is part of a 3-part series on Clones, including: Clone FAQs - KB0715621Clone Tips and Tricks - KB1214621 width: 70%; .mce-toc { background-color: #f7f7f7; padding: 10px; border-radius: 5px; border: 1px solid #dedede; min-width: 500px; } Table of Contents How does the clone work?Can I roll back my clone?What do all the options do for cloning?Where do I configure the data preserver?Can I clone over my production instance and how?How to do a full clone? How does the clone work? In response to a clone request, the ServiceNow platform performs the following tasks: Generates a file to preserve operational data on the target server. This file contains the data preserved by data preservers.Creates a new database for the target instanceRestores the database schema and data from the latest backup to the newly created databaseAfter all data is copied across it starts the exclude/preserver functionsIf Exclude options are ticked Tables in the exclude module are truncated (All data is cleared out) (unless this is TPH table where it will be deleted) File created in Step 1 for preservers is loaded into the target database (overwriting any data from the restore)Email functionality is disabled in the target databaseOnce all is completed the target instance repoints to the newly created databaseAll Clone cleanup scripts are executed in the target instance. Regenerate Text indexesClear scheduled job node associations The clone is complete and the instance is accessible for the customer.After the clone completes a backup is taken of the old Target database Once the backup completes the old target database is retired. Can I roll back my clone? As we take a backup of the database after the cloning process we can roll back the clone up to 7 days after the clone was run. After a clone is complete there is a UI action 'Rollback clone' if you click this button it will roll back the clone using the same automation that Technical Support will use to roll back the clone. Any issues faced or clarification about the rollback of a clone please contact Technical Support and we will be happy to help. What do all the options do for cloning? Clone options Field Description Exclude tables specified in Exclusion List Prevents cloning records from the source instance specified in the System Clone > Exclude Tables module. Use this option to create empty but usable tables on the target instance. By default, the system excludes tables for auditing, license usage, logging, and notifications. This option is selected by default. Note: The legacy clone engine does not support this option. Exclude audit and log data Prevents cloning audit and log records from the source instance. Use this option to create empty but usable audit and log tables on the target instance. This option is selected by default. Exclude large attachment data Prevents the cloning of large attachments such as video files, image files, and other large binary file types. Use this option to exclude all common binary file types, regardless of file size. When selected, the clone also excludes attachments from the Attachments [sys_attachment] and Attachment Documents [sys_attachment_doc] tables that meet all these criteria. The attachment table_name value does not indicate that it is a small file. Small attachments have table-name values that start with ZZ_.The attachment data type value indicates that it is a large file such as an application or video.The attachment table_name is not one of these system tables: sys_certificate, ecc_agent_jar, ecc_agent_mib, sys_store_app, or invisible.sys_store_app. This option is selected by default. Preserve theme Preserves the theme and CSS elements on the target clone. This option is selected by default. Lock settings for this clone request If you use a clone profile, this option locks the settings and options at the time of the clone request. Any subsequent changes to the clone profile, regardless of when the clone runs, do not affect the clone request. This option is not selected by default. Amount of data copied from large tables Clones the number of days of historical data from large source tables, including task, pa_scores, and metric_instance. By default, the target instance receives the latest 90 days of historical data from the source instance. Preserve In Progress Update Sets Preserves update sets during the clone process. This option eliminates the need to export in-progress, global update sets before you initiate a clone. The default is none. You can select the latest 90 days to preserve the in-progress update sets during this time. Note: Review and commit the update sets after the clone. Preserve users and related tables Prevents users and user-related tables from being overwritten on the target clone. This option is not selected by default. Clone frequency Defines how often this target automatically receives clone data and the maximum number of occurrences. By default, the clone frequency is set to None. For more information about scheduling cloning, see Schedule cloning. For more information, Request a Clone. Where do I configure the data preserver? Data preserver applied to the clone target is configured on the clone source from where the clone is requested. Can I clone over my production instance and how? This is risky and would advise against it but in some cases, you may want to perform a clone over your production instance, this may be for a go-live if your instance is already live this is not a good idea, and would advise you to contact Technical Support for assistance. To add your production instance as a clone target you can follow the below steps: Log in to your production instanceGo to the system properties listFind system property: glide.db.clone.allow_clone_targetSet this to 'true' This will now allow this instance to be created as a clone target Cloning over this instance is the same as any other request for a clone. After cloning is complete this property should be then set back to 'false' so you don't accidentally clone over your prod instance late. How to do a full clone? A full clone is when you bring over all the information from your source instance and you do not exclude any data from source. This is normally done when you want a full replica of your prod instance with logs, emails, etc. This is helpful when doing upgrade, update set, application deployment, etc to see how it would run on your production instance. To request a full clone, when requesting the clone, please uncheck all the exclude options: Exclude audit and log data - UncheckedExclude large attachment data - UncheckedExclude tables specified in Exclusion List - UncheckedPreserve Theme - CheckedAmount of data copied from Large Tables - Full To Note: Emails are disabled during the clone, so even though emails were copied across they will not send after a full clone.