Clean alert history and impact status tables

task brazil Updated Sep 10, 2026 1 min read clean-alert-tables.md

Schedule jobs to mark and remove old alert records in the Alert History [em_alert_history] and Impact Status [em_impact_status] tables, to prevent the tables from becoming overloaded with data.

Before you begin

Role required: evt_mgmt_admin

About this task

Schedule the following jobs to remove old alert records:

Backfill: Determines when alerts are to be marked for deletion.
Clean: Deletes the alerts.

Note: The records in the [em_alert_history] and [em_impact_status] tables are deleted by default after three months. This is controlled by the properties evt_mgmt.impact_calculation.cleanup_age_seconds.em_alert_history and evt_mgmt.impact_calculation.cleanup_age_seconds.em_impact_status. The default value is 7,776,000 seconds (equivalent to 90 days).

Procedure

Navigate to All > System Definition > Scheduled Jobs.

The Scheduled Jobs page appears.
To determine how often to mark alerts for deletion on the Impact Status table:
1. Locate and select the Event Management - Backfill Impact Status Table job.
  
  The Scheduled Script Execution page appears.
  
  [Omitted image "scheduled-script-execution.png"] Alt text: Scheduled Script Execution page
2. In the Repeat Interval field, configure how often you want the job to run.
  
  To run the job immediately, select Execute Now.
3. Select Update.
To remove old alerts from the Impact Status table:
1. Locate and select the Event Management - Clean Impact Status Table job.
  
  The Scheduled Script Execution page appears.
  
  [Omitted image "scheduled-scipt-execution-clean.png"] Alt text: Scheduled Script Execution page
2. In the Repeat Interval field, configure how often you want the job to run.
  
  To run the job immediately, select Execute Now.
3. Select Update.
Repeat steps 2 and 3 to perform the Backfill and Clean jobs on the Alert History Table.

Parent Topic:Purge impact status and alert history

71 lines · 3.3 KB Wrap lines

---
title: Clean alert history and impact status tables
description: Schedule jobs to mark and remove old alert records in the Alert History \[em\_alert\_history\] and Impact Status \[em\_impact\_status\] tables, to prevent the tables from becoming overloaded with data.
locale: en-US
canonical_url: https://www.servicenow.com/docs/r/it-operations-management/event-management/clean-alert-tables.html
release: brazil
product: Event Management
classification: event-management
topic_type: task
last_updated: "2026-09-10"
reading_time_minutes: 1
breadcrumb: [Purge impact status and alert history, Rotate event and alert table for cleanup, Manage and monitor alerts, Configure, Event Management, ITOM AIOps, IT Operations Management]
---

# Clean alert history and impact status tables

Schedule jobs to mark and remove old alert records in the Alert History \[em\_alert\_history\] and Impact Status \[em\_impact\_status\] tables, to prevent the tables from becoming overloaded with data.

## Before you begin

Role required: evt\_mgmt\_admin

## About this task

Schedule the following jobs to remove old alert records:

- **Backfill**: Determines when alerts are to be marked for deletion.
- **Clean**: Deletes the alerts.

**Note:** The records in the \[em\_alert\_history\] and \[em\_impact\_status\] tables are deleted by default after three months. This is controlled by the properties **evt\_mgmt.impact\_calculation.cleanup\_age\_seconds.em\_alert\_history** and **evt\_mgmt.impact\_calculation.cleanup\_age\_seconds.em\_impact\_status**. The default value is 7,776,000 seconds \(equivalent to 90 days\).

## Procedure

1. Navigate to **All** &gt; **System Definition** &gt; **Scheduled Jobs**.

The **Scheduled Jobs** page appears.

2. To determine how often to mark alerts for deletion on the **Impact Status** table:

1. Locate and select the **Event Management - Backfill Impact Status Table** job.

The **Scheduled Script Execution** page appears.

\[Omitted image "scheduled-script-execution.png"\] Alt text: Scheduled Script Execution page

2. In the **Repeat Interval** field, configure how often you want the job to run.

To run the job immediately, select **Execute Now**.

3. Select **Update**.

3. To remove old alerts from the **Impact Status** table:

1. Locate and select the **Event Management - Clean Impact Status Table** job.

The **Scheduled Script Execution** page appears.

\[Omitted image "scheduled-scipt-execution-clean.png"\] Alt text: Scheduled Script Execution page

2. In the **Repeat Interval** field, configure how often you want the job to run.

To run the job immediately, select **Execute Now**.

3. Select **Update**.

4. Repeat steps [2](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/it-operations-management/event-management/clean-alert-tables.md) and [3](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/it-operations-management/event-management/clean-alert-tables.md) to perform the Backfill and Clean jobs on the **Alert History Table**.

**Parent Topic:**[Purge impact status and alert history](https://raw.githubusercontent.com/ServiceNow/ServiceNowDocs/brazil/markdown/it-operations-management/event-management/t_EMConfigurePurge.md)