Exploring Instance Clone
Summarize
Summary of Exploring Instance Clone
Instance Clone allows you to copy an entire database from one ServiceNow instance to another, ensuring synchronization across environments. This process is crucial for testing changes, such as upgrades or new applications, in a representative environment before going live. Cloning minimizes discrepancies between instances, facilitating smoother deployments.
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Key Features
- Clone Workflow: The cloning process involves several steps: build configuration, preflight checks, backup, pre-clone preparation, database interface provisioning, restoration, exclusion of specified tables, preservation of certain data, node repointing, and post-clone cleanup.
- User Roles: Administrators with the cloneadmin role can manage clones by requesting, scheduling, modifying, or canceling them.
- Clone Benefits: You can tidy up data with exclusions and preserve specific data types, ensuring consistent outcomes through defined clone profiles.
- Cross-Version Cloning: Cloning is possible between instances on different versions; the target instance will adopt the source instance's version.
- Backup Utilization: Cloning uses recent daily backups, which are at most 36 hours old, ensuring data accuracy and relevancy.
- Production Cloning: Instances can act as clone targets if a specific system property is enabled, but should be disabled afterward to prevent accidental overwrites.
Key Outcomes
Utilizing Instance Clone facilitates effective testing and deployment of changes, reduces environment divergence, and ensures data integrity across instances. By understanding the cloning process and its configurations, ServiceNow customers can optimize their instance management and enhance operational efficiency.
Explore how to use a clone to copy everything in a database from one instance to another.
Instance Clone overview
- Cloning helps reduce divergence between the environments and promotes smooth deployments.
- Cloning is used to test changes such as upgrades, new applications, and new capabilities.
- Cloning data comes from the most recent daily backup.
A list of helpful terminology and definitions for clone is included here Clone terminology.
Instance Clone workflow
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Clone build configuration: Basic definitions, configurations, and profile options are prepared. Data to be included, excluded, or preserved is verified.
- Preflight checks: The clone checks the source and target instances to verify that they are in a healthy state before proceeding with the clone.
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Backup: Uses the latest daily backup. If there were major recent changes, a new backup is created. You can also trigger a new backup manually by selecting the On-demand backup via the Clone Admin Console.
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Pre-Clone: Prepares space for the new database before restoring it.
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Provision database interface (DBI): A new target instance is set up to receive the restored data.
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Restore: The backup data is restored to the new target instance.
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Exclusions: Tables marked for exclusion are deleted.
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Preservers: Data is preserved from the old target (pre-clone instance) and is copied to the new target instance.
- Node repoint: The system switches from the old target to the new clone without user disruption.
- Scheduling scripts: Cleanup scripts and custom scripts are scheduled to run. Scripts with the same priority run at the same time.
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Post Clone: Cleanup scripts run.
Instance Clone users
| User | Description |
|---|---|
| Administrator | Clone admins with the clone_admin role can request, cancel, schedule, or modify clones. |
Clone benefits
| Benefit | Feature |
|---|---|
| Tidy up data with exclusions and preservers for specific clone scenarios. | Definitions |
| Establish consistent clone outcomes with clone profiles and registered instances. | Configurations |
| Copy data from a production instance to a non-production instance or to copy data between non-production instances. | Request a clone |
Instance Clone use cases
Clone to a different version
You can clone between instances that are on different family release versions. During a clone, the source version replaces the target version. For example, if you clone from Source (Zurich) to Target (Yokohama) the target will match the source after the clone and be on Zurich release.
Clone from a backup
The clone uses data from the most recent, daily backup of the source instance when cloning. Backups that are used for cloning are a maximum of 36 hours old. A clone from backup starts only at the date and time processing that it's scheduled to start.
If the source and target instances are on different versions of the ServiceNow AI Platform, the target instance is modified to match the source instance version during this time.
When starting a clone from a backup, the date and time the backup was taken, as well as periodic progress messages, appear in the Clone Log related list.
Clone over production instances
As long as the system property glide.db.clone.allow_clone_target is TRUE, an instance can serve as a clone target. Please ensure the property glide.db.clone.allow_clone_target is set back to FALSE after a production instance has served as a clone target. This helps prevent accidental or unintended clones over production in the future.
Deprecated Clone Options
For more information about using Clone Admin Console instead of the legacy Instance Clone, see KB1425858: Clone Admin Console: Quick Start Guide & Instructions.