--- sourceDocument: Brazil IT Operations Management sourceDocumentLink: https://www.servicenow.com/docs/r/it-operations-management Release : - brazil ft:locale : - en-US ft:publication_title : - Brazil IT Operations Management ft:clusterId : - itom bundleId : - itom workflow : - Technology --- # ECC queue for Discovery # The ECC queue for Discovery {#ariaid-title1} Release version: Brazil Updated September 10, 2026 ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 3 minutes to read Summarize ![AI sparkle icon](https://servicenow.com/docs/portal-asset/ai-sparkle-icon) Summarized using AI This content was generated using new OpenAI-powered functionality. Results are provided on an as is basis and are not guaranteed to be accurate or complete. ## Summary of The ECC queue for Discovery The External Communication Channel (ECC) Queue is a critical integration point between your ServiceNow instance and external systems, most notably the MID Server, used during Discovery processes. It holds messages exchanged between the instance and target systems, categorized as output (instructions sent to targets) and input (data received from targets). These records provide a detailed flow of probe and sensor activities, including XML payloads involved in asset discovery. Show full answer Show less ## Managing ECC Queue Records As Discovery runs, the ECC queue can grow substantially, often reaching several gigabytes. While many completed task records are unnecessary, some are valuable for troubleshooting issues such as incomplete data capture on specific devices. To balance data retention and storage, records older than 7 days are automatically deleted by default. However, customers can configure the deletion schedule and table rotations (eccqueueevent and eccqueue) to retain data for at least a month, which is recommended for effective issue resolution. ## Accessing and Monitoring the ECC Queue ServiceNow customers can access the ECC queue through the following navigation paths: * Discovery \> Output and Artifacts \> ECC Queue * ECC \> Queue Within the queue, records display states such as **ready** , **processing** , **processed** , and **error**, reflecting the lifecycle of probe instructions and results. Monitoring these states helps track discovery progress and identify errors for troubleshooting. ## Processing and Troubleshooting ECC Queue Records ECC queue input records are processed by business rules, though not all inputs are immediately processed and some may remain in a ready state. Errors encountered during processing change the record state to **error**, providing a starting point for diagnostics. For detailed debugging, use a script debugger in the same session to review the business rule and payload processing code related to the ECC queue record. ## Configuration Properties ServiceNow provides properties to control ECC queue behavior, such as a setting to preserve attachments to ECC queue entries instead of deleting them after successful sensor processing. This is useful for debugging purposes. Customers can manage these properties in **Discovery Definition \> Properties**. The External Communication Channel (ECC) Queue is a connection point between your ServiceNow instance and other systems that integrate with it, most commonly a MID Server.{#r_DiscoveryStatusECCQueue__ph_ecc-queue-intro} ## Contents of the ECC Queue {#r_DiscoveryStatusECCQueue__section_cjh_4cr_ccb} The ECC queue contains records that are created during all stages of discovery. Each record is a message from the instance to system your are targeting for discovery, classified as output, or a message from that system to the instance, classified as input. {#r_DiscoveryStatusECCQueue__p_ecc-queue-content} ECC queue records provide you with a connected flow of probe and sensor activity along with the XML payload sent to or from an instance and the assets you're targeting. ## Automatic deletion of ECC queue records {#r_DiscoveryStatusECCQueue__section_z4h_4cr_ccb} As your IT Asset Discovery runs, the size of the ECC queue can grow to several gigabytes. Most of the "completed tasks" records are unnecessary, but some might be important for issue resolution. For example, if Discovery is not properly capturing the disk drives on a particular Windows server, you can look in the ECC Queue at the data returned by the Windows - System Information probe. For this reason, you should retain ECC Queue data from Discovery for at least a month. By default, records in the ECC Queue older than 7 days are deleted automatically. You can set the deletion schedule by updating the ECC queue (as we will explain in the next section) and the table rotation schedule. The table rotation names are: * ecc_queue_event * ecc_queue {#r_DiscoveryStatusECCQueue__ul_jx3_5cr_ccb} ## Accessing the ECC queue {#r_DiscoveryStatusECCQueue__section_djh_4cr_ccb} You can access the ECC queue from either of these locations: * DiscoveryOutput and ArtifactsECC Queue * ECCQueue {#r_DiscoveryStatusECCQueue__ul_nj3_gfp_qbb} The following image is an example of a record in the ECC queue. This record shows that a ConnectorProbe was instructed to run and has been processed. Note the XML payload it returned as the discovery task collected data. See [The MID Server ECC queue](https://www.servicenow.com/docs/access?context=ecc-queue-mid-server&version=brazil&pubname=brazil-servicenow-platform&ft:locale=en-US) for a description of each field. Figure 1. An example ECC queue record ## ECC queue states Input and output messages keep processing until the discovery is finished or terminated. You can monitor the ECC queue to see records populate during discovery and see the states of each record change. ECC queue input records are processed by business rules (BR), but not all business rules direct these ECC queue inputs to process. As a result, some ECC queue inputs remain in a ready state. The process is as follows: 1. When new probe instructions are available for the MID Server, the system creates an output record with the state of ready. 2. The MID Server then starts processing the probe instructions and the state changes to processing before it finally changes to processed. 3. When a result returns to the MID Server and is ready to be sent to the instance, the system creates an input record with the state of ready. 4. While the system processes the payload, the state changes to processing before it finally changes to processed. If any errors are encountered, the state changes to error. You can review errors as a starting point for troubleshooting a failed discovery. {#r_DiscoveryStatusECCQueue__ol_gww_ls4_lz} ## Debug processing of ECC queue records {#r_DiscoveryStatusECCQueue__section_exh_c3r_pvb} To use a script debugger, process the payload on the same session as the debugger. Review the business rule which processes the particular ECC queue record and the actual code which processes the payload. ## Properties and parameters that affect the ECC queue These properties are available to control aspects of the ECC queue:{#r_DiscoveryStatusECCQueue__table_khy_354_lz__entry__2} | Property | Description | |-|-| | Save ECC queue attachments | The normal behavior for Discovery sensors is to delete attachments to ECC queue entries on successful sensor processing. Enabling this property overrides this behavior, and forces attachments to be preserved. This is typically done for debugging purposes. To enable this property, navigate to Discovery DefinitionProperties. | [ ] {#r_DiscoveryStatusECCQueue__table_khy_354_lz} **Related topics** * [Manage ECC Queue content for a MID Server](https://www.servicenow.com/docs/access?context=ecc-queue-mid-server&version=brazil&pubname=brazil-servicenow-platform§ion=manage-ecc-queue-content&ft:locale=en-US) *[\>]: and then