--- sourceDocument: Australia IT Operations Management sourceDocumentLink: https://www.servicenow.com/docs/r/australia/it-operations-management Release : - australia ft:locale : - en-US ft:publication_title : - Australia IT Operations Management ft:clusterId : - itom bundleId : - itom workflow : - Technology --- # Pattern-based discovery # Pattern-based discovery in Service Mapping {#ariaid-title1} Release version: Australia Updated March 12, 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 Pattern-based discovery in Service Mapping Pattern-based discovery is Service Mapping's primary method for gathering data about devices and applications that compose application services. It enables ServiceNow customers to create detailed maps of application services and store this information in the CMDB. The discovery process identifies configuration items (CIs) and their connections by using predefined patterns---sequences of commands designed to detect CI attributes and outbound connections. Show full answer Show less ## Key Features * **Entry Points:** Discovery starts from an entry point, such as an IP address or hostname, which represents where clients access a service instance. * **Horizontal and Top-down Discovery:** Initially, horizontal discovery identifies the host device. Then, top-down discovery maps applications running on that host. * **MID Servers:** Communication with devices is performed through MID Servers located within the organization's network, avoiding firewall traversal. * **Discovery Process:** Includes creating discovery requests, using Shazzam probes for port discovery, and sequentially running classification, identification, and exploration probes. * **Pattern Operations:** Patterns consist of identification sections (to match CIs) and connectivity sections (to find outbound connections). * **Connection Enrichment:** Discovered CI connections are enriched by checking additional CMDB tables (cmdbtcp and saflowconnection) for unique data not found by patterns. * **Boundaries:** Discovery stops at CIs marked as boundaries or those without outbound connections to prevent endless mapping loops. * **Service Recomputations:** Regular recomputation updates the service maps with the latest CI changes, network and storage paths, and applies impact rules. ## Important Considerations * Pattern operations currently only support English; non-English data may cause discovery failures. * Service Mapping creates and updates records in the Mapped Application Service \[cmdbciservicediscovered\] table to represent service instances. ## Practical Benefits for ServiceNow Customers This pattern-based discovery approach enables customers to accurately and efficiently map application services and their underlying infrastructure. It helps ensure CMDB accuracy by automatically discovering hosts, applications, and their interconnections. Customers can expect comprehensive service maps that support impact analysis, troubleshooting, and service assurance. Pattern-based discovery is the main method of Service Mapping collecting data about devices and applications used in application services. After Service Mapping collects data, it then creates a map of application services and stores the collected data in the CMDB. ServiceNow applications refer to devices and applications that comprise a service instance as configuration items (CIs). Service Mapping uses patterns to discover and map CIs. A pattern is a sequence of commands designed to detect attributes of a CI and its outbound connections. A typical Service Mapping pattern consists of two types of algorithms for identifying CIs and finding CI connections. The starting point of any discovery process is an entry point. An entry point is a point where clients access a service instance. For example, to map your electronic mailing service instance, define an IP address or host name of the email server as an entry point. The discovery and mapping process begins from Discovery performing the horizontal discovery to identify the host. Once the host discovery is complete, Service Mapping starts the top-down discovery to find and map applications running on this host. Service Mapping uses MID Servers to communicate with CIs in your organization. MID Servers are located inside your organization network and Service Mapping can communicate with them without traversing firewalls. Note: Currently, pattern operations do not support multi-languages. If values returned from pattern operations are not in English, the returned data cannot be parsed properly and the pattern discovery will fail. The discovery and mapping process consists of the following interactions: 1. An administrator defines an service instance with an entry point for an application CI. Service Mapping creates a record for the new service instance in the Mapped Application Service \[cmdb_ci_service_discovered\] table. 2. The device hosting the application is identified. 1. Service Mapping checks if the device hosting this application CI exists in the CMDB. 2. If the device hosting this application CI does not exist, Service Mapping triggers Discovery to detect host. 3. Discovery creates the first set of probes for port discovery, referred to as Shazzam probes. It places them as a discovery request in the External Communication Channel (ECC) queue. 4. The MID Server checks the ECC queue and retrieves the discovery request assigned to it. 5. The MID Server runs the probes against the host and discovers open ports. 6. The MID Server passes information on the host ports to the ECC queue. 7. Discovery checks the ECC queue and receives information on the host ports. 8. These steps are repeated for other types of probes: classification, identification, and exploration. 9. Discovery adds the host to the CMDB. 10. During the host discovery using probes, Service Mapping checks the ECC queue if this process is complete. When the host discovery is complete, Service Mapping checks whether this host exists in the CMDB. {#pattern-based-discovery__ol_nmh_grh_dx} Note: For the detailed description of the horizontal discovery flow, refer to [Horizontal discovery process flow with probes and sensors](https://www.servicenow.com/docs/Af~VFnWMDR7QiImX9LEh7Q "The horizontal discovery process passes through the four phases of discovery using probes, which gather information on the target machine. Sensors then help Discovery determine what to do with that information."). 3. Once the host is found in the CMDB, Service Mapping discovers the application running on this host. 1. Service Mapping creates an application discovery request for the IP address of the entry point. It then writes the request in the ECC queue and assigns a MID Server to the request. 2. The MID Server checks the ECC queue and retrieves the discovery request assigned to it. 3. The MID Server starts running identification sections of the patterns associated with the classifier to find the match for the entry point. When the identification section matches the entry point, the pattern discovers a CI. 4. The MID Server starts running connectivity sections of the pattern to find outgoing connections of the newly discovered CI. 5. The MID Server passes information on the discovered CI, its attributes, and connections to the ECC queue. 6. Service Mapping checks the ECC queue and receives information on the newly discovered CI. Whenever Service Mapping checks the ECC queue and receives information on a discovered CI, it checks these tables for any data on outbound connections related to the CI: the cmdb_tcp and sa_flow_connection tables. If these two tables contain unique data that patterns did not discover, Service Mapping enriches the information about the CI connections and adds them to the map. 7. Service Mapping writes the information into the CMDB and adds this CI to the service instance map. 8. Service Mapping creates the discovery requests for all applications to which the newly discovered CI connects. Mapping is complete after Service Mapping maps a CI that either does not have any outbound connections or is marked as a boundary. A boundary makes Service Mapping stop discovery from this point and not follow outgoing connections. {#pattern-based-discovery__ul_rfq_rth_dx} 4. The system regularly runs the service recomputation to query the CMDB for the latest CI changes, add data for network and storage paths, and apply CI impact rules. {#pattern-based-discovery__ul_crj_tgf_lt} **Related concepts** * [Horizontal discovery process flow with probes and sensors](https://www.servicenow.com/docs/Af~VFnWMDR7QiImX9LEh7Q "The horizontal discovery process passes through the four phases of discovery using probes, which gather information on the target machine. Sensors then help Discovery determine what to do with that information.") * [Traffic-based discovery in Service Mapping](https://www.servicenow.com/docs/Nc~BmgMGFb2e4_PVEPNMaw "Service Mapping can discover and map configuration items (CIs) following their traffic-based connections. This method is referred to as traffic-based mapping and complements pattern-based mapping.") **Related reference** * [The ECC queue for Discovery](https://www.servicenow.com/docs/BVFgMoSEO4IOOWIXFgUsrA "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.") **Related topics** * [Service instances (Application services)](https://www.servicenow.com/docs/access?context=application-services&version=australia&pubname=australia-servicenow-platform&ft:locale=en-US)