Exploring Auditing
Summarize
Summary of Exploring Auditing
Auditing in ServiceNow enables tracking of creation, update, and deletion changes on auditing-enabled tables, helping organizations maintain comprehensive records of data modifications. By default, tables like Incident, Change, and Problem are audited. Customers can configure auditing to track entire tables or specific fields, ensuring detailed change histories while managing system performance.
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Key Features
- Table and Field Auditing: Auditing can be enabled for entire tables or selectively for individual fields using dictionary attributes, supporting both inclusion and exclusion listing approaches.
- Auditing Parent and Child Tables: Audit settings do not inherit between parent and child tables; each table must be enabled separately for auditing.
- System Table Auditing: By default, deletions on system tables are not audited. To enable auditing on system tables, they must be added to the
glide.ui.auditdeletedtablesproperty list. - Deletion Auditing: Deletions from forms are audited by default unless the
noauditdeletedictionary attribute is set. Deletions from lists are audited when enabled and not excluded via theglide.db.audit.ignore.deleteproperty. - Non-Cancellable Audit Records: With the Xanadu release, audit records are created immediately within the same transaction to prevent loss of audit data if a transaction is cancelled. This behavior is controlled by the
glide.db.audit.lazyproperty, which defaults to False for improved reliability.
Auditing Data Details
Auditing records capture key information including:
- Unique record identifier (sysid)
- Changed field name
- Old and new values
- Number of updates to the record and field
- Date and time of change
- User who made the change
- Reason for the change, if provided
- Internal checkpoint ID for versions
Performance Considerations and Exclusions
Auditing high-traffic system tables may impact performance; therefore, auditing entire tables such as emalert is not recommended. Instead, audit selected fields of interest. Auditing excludes certain updates, including those made by upgrades, import sets, system fields (except sysclassname and sysdomainid), and updates triggered by UI Pages or inactivity monitors. This filtering prevents excessive audit noise and preserves system performance.
Practical Guidance for ServiceNow Customers
- Enable auditing on tables and fields relevant to your compliance and operational needs while minimizing performance impacts by auditing only necessary fields.
- Use dictionary attributes to exclude fields from auditing when full table auditing is enabled.
- Manually add and configure system properties like
glide.ui.auditdeletedtablesandglide.db.audit.ignore.deleteto customize audit behavior for system tables and deletion events. - Leverage the enhanced non-cancellable audit process introduced in the Xanadu release for improved audit reliability; ensure the
glide.db.audit.lazyproperty is removed or set to False to benefit from this feature.
Track record changes on auditing-enabled tables. By default, the system tracks changes to the incident, change, and problem tables, among others.
Enabling auditing tracks the creation, update, and deletion of all records in the table. If you want to audit individual fields in a table, you can hide fields you don’t want to track using a dictionary attribute.
- The Audit table.
- The Knowing about History sets table.
Auditing parent and child tables
- For example, if you enable auditing for the Configuration Items [cmdb_ci] table, only CIs stored in that base table are audited.
- Likewise, if you enable auditing for the Computers [cmdb_ci_computer] table, only the computer CI records are audited, including any fields on the Computers [cmdb_ci_computer] table that is derived from the Configuration Items [cmdb_ci] table.
Auditing system tables
By default, the system doesn’t audit the deletion of a record from system tables. To audit a system table, add it to the list of tables in the glide.ui.audit_deleted_tables property list.
Auditing deletions from a form or list
By default, the system audits deletions of individual records from a form. To prevent auditing, set the table's dictionary attribute no_audit_delete.
glide.db.audit.ignore.delete =
sys_mutex,sys_db_cache,sys_lucene_block,sys_lucene_file,sys_lucene_directory,sys_user_preference,sys_audit,sc_cart,sc_cart_item,sys_trigger,wf_context,wf_activity,wf_condition,wf_executing,wf_history,wf_log,wf_transition,wf_transition_history,
cmdb_ci_windows_service, cmdb_sam_sw_install, cmdb_software_instance, cmdb_sam_sw_usage, sam_sw_counter_detail
To learn more about adding system properties, see Add a system property
It is to be noted that by default, the audit deletes are enabled whether the record is deleted from the form view, list view, or through a script/scheduled job.
Information audited
Auditing tracks the following record changes:- Unique Record Identifier (sys_id) of the record that changed
- Field that changed
- New field value
- Old field value
- Number of times this record and field have been updated
- Date and time when the change occurred
- User who made the change
- Reason for the change (if any reason is associated with the change)
- Internal checkpoint ID for the record, if the record has multiple versions.
Information exempted from auditing
Some updates aren’t audited despite enabling auditing on a table. For example, you may see 132 updates in a record's history, but only seven audited ones.- Updates made by an upgrade.
- Updates are made through import sets.
- Records in parent or child tables.
- Fields with the no_audit dictionary attribute.
- System tables are not listed in the glide.ui.audit_deleted_tables property list.
- Fields that begin with the sys_ prefix (system fields), except the sys_class_name and sys_domain_id columns.
- UI Pages can sometimes trigger updates to a record without creating an audit log.
- Anytime an inactivity monitor touches a record. It prevents you seeing possibly hundreds of updates listed against an incident, with the noise drowning out the useful data.
- Manual changes to Performance Analytics scores.
- Applying Update Set
- Import XML
Auditing a table
For instructions on how to audit a table, see Configuring auditing for a table.- You can enable auditing for the entire table, then exclude those fields you don’t want to include. It’s appropriate when you want to audit most, but not all, fields, and is referred to as an exclusion listing. For more information, see Exclude a field from being audited (exclusion listing).
- You can enable auditing for the table, but only for specified fields. It’s appropriate when you want to audit only a small number of the table's fields and is referred to as an inclusion listing. For information on how to include a field using an inclusion listing, see Including a table field in auditing (inclusion listing).
Non-cancellable audit records
Reduce the chances of audit records not being recorded when a transaction is canceled with the new default setting.
glide.db.audit.lazy property is set to True, the enhanced audit process is disabled.glide.db.audit.lazy property from True to False.
This property is not usually defined in the Properties table because the majority of instances start using the new default value and behavior. On some instances, this property might be already present and set as True, which means
that these instances won’t be able to use this change to audit behavior.