<h2>Discovery probes and sensors</h2><br/><div style="overflow-x:auto"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head><meta content="text/html; charset=UTF-8" /><meta name="copyright" content="(C) Copyright 2024" /><meta name="DC.rights.owner" content="(C) Copyright 2024" /><meta name="generator" content="DITA-OT" /><meta name="DC.type" content="concept" /><meta name="DC.title" content="Discovery probes and sensors" /><meta name="abstract" content="Discovery probes and sensors perform data collection and update the CMDB." /><meta name="description" content="Discovery probes and sensors perform data collection and update the CMDB." /><meta name="DC.subject" content="Discovery, probes, sensors" /><meta name="keywords" content="Discovery, probes, sensors" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/reference/r-discovery.html" /><meta name="DC.relation" scheme="URI" content="../../../product/it-operations-management/reference/r_ITOMApplications.html" /><meta name="DC.relation" scheme="URI" content="../../../product/it-operations-management/reference/itom-visibility-landing-page.html" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/reference/r_ListOfDiscoveryProbes.html" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/reference/r_Sensors.html" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/reference/r_Probes.html" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/task/t_AlignVerCustProbeSens.html" /><meta name="DC.relation" scheme="URI" content="../../../product/discovery/reference/r_MultiprobesIncludedWithDiscovery.html" /><meta name="DC.relation" scheme="URI" content="../../../script/server-scripting/task/t_CustomProbeTextFile.html" /><meta name="DC.creator" content="ServiceNow" /><meta name="DC.date.created" content="2022-08-04" /><meta name="DC.date.modified" content="2022-08-04" /><meta name="mini-toc" content="yes" /><meta name="DC.format" content="XHTML" /><meta name="DC.identifier" content="c_DiscoveryProbesAndSensors" /><link rel="stylesheet" type="text/css" href="../../../CSS/commonltr.css" /><title>Discovery probes and sensors</title></head><body id="c_DiscoveryProbesAndSensors"> <div class="breadcrumb"><a class="link" href="../../../product/it-operations-management/reference/r_ITOMApplications.html" title="Get better visibility into your infrastructure and services, prevent service outages, and expand your organization's operational agility with ServiceNow IT Operations Management.">IT Operations Management</a> > <a class="link" href="../../../product/it-operations-management/reference/itom-visibility-landing-page.html" title="The ServiceNow ITOM Visibility product consists of ServiceNow Discovery, ServiceNow Service Mapping, Certificate Inventory and Management, Service Graph Connectors, Multisource CMDB, and Firewall Audits and Reporting. Discovery and Service Mapping give you a unified, connected view of your entire IT network and the services that it supports.">ITOM Visibility</a> > </div> <h1 class="title topictitle1" id="ariaid-title1">Discovery probes and sensors</h1> <div class="body conbody"><p class="shortdesc"><span class="ph">Discovery</span> probes and sensors perform data collection and update the CMDB.</p> <div class="section" id="c_DiscoveryProbesAndSensors__section_rlg_sxf_dcb"> <p class="p">With each release, patterns are replacing many probes and sensors for Discovery. Consider creating new patterns or editing existing ones if you want to customize what Discovery can find. The information on probes and sensors is intended for customers who are not using patterns yet and for customers who already have customized probes that are retained upon upgrade. See <a class="xref" href="c-UsingPatternsForHorizontalDiscovery.html" title="A pattern is a series of operations that tell Discovery which CIs to find on your network, what credentials to use, and what tables to populate in the CMDB.">Patterns and horizontal discovery</a> for more information on patterns.</p> <div class="p"><div class="note"><span class="notetitle">Note:</span> Probe to pattern migration is supported for the New York release and later. See the knowledge article <a class="xref" href="https://support.servicenow.com/kb_view.do?sysparm_article=KB0694477" target="_blank" rel="noopener noreferrer">KB0694477</a> for more information.</div> </div> </div> <div class="section" id="c_DiscoveryProbesAndSensors__section_ug3_fv2_dcb"><h2 class="title sectiontitle">Discovery phases</h2> <p class="p">Discovery always uses probes and sensors during the first two phases of discovery: scanning and classification. For the last two phases, identification and exploration, Discovery can use probes and sensors or patterns. This topic refers to probes and sensors only. See <a class="xref" href="c_GetStartedWithDiscovery.html" title="Discovery finds computers, servers, printers, a variety of IP-enabled devices, and the applications that run on them. It can then update the CIs in your CMDB with the data it collects.">Discovery basics</a> for an explanation of these phases. See <a class="xref" href="c-UsingPatternsForHorizontalDiscovery.html" title="A pattern is a series of operations that tell Discovery which CIs to find on your network, what credentials to use, and what tables to populate in the CMDB.">Patterns and horizontal discovery</a> for more information on patterns.</p> </div> <div class="section" id="c_DiscoveryProbesAndSensors__section_zh4_dv2_dcb"><h2 class="title sectiontitle">Probes, sensors, and the ECC queue</h2> <div class="p">The probe collects the information and the sensor processes it. Both get their instructions from the ECC queue. There is a worker job on the MID Server that monitors the queue for work. The monitor checks for any entries where the <span class="keyword option">Queue</span> is <span class="keyword option">output</span> and the <span class="keyword option">State</span> is <span class="keyword option">ready</span>.<div class="fig fignone" id="c_DiscoveryProbesAndSensors__fig_slp_hz5_tp"> <img class="image" id="c_DiscoveryProbesAndSensors__image_t43_pz5_tp" src="../image/ECCQueueOutput.png" alt="The ECC queue" /> </div> </div> <div class="p">The MID Server then processes all the output ECC messages, runs the necessary probes, and returns the probes results to the ECC queue. These results are put in the ECC Queue as <span class="keyword option">input</span> entries.<div class="fig fignone" id="c_DiscoveryProbesAndSensors__fig_pkv_sz5_tp"><span class="figcap"><span class="fig--title-label">Figure 1. </span>ECC queue input</span> <img class="image" id="c_DiscoveryProbesAndSensors__image_vw1_vz5_tp" src="../image/ECCQueueInput.png" alt="ECC queue record" /> </div> </div> <p class="p">After an entry is inserted in the ECC Queue table, a business rule fires (on insert) that takes that information and runs it through a <span class="keyword option">sensor processor</span>. The sensor processor's job is to take the input data, find any sensors interested in that data, and pass it along to be processed. Those sensors ultimately update the CMDB.</p> </div> <div class="section"><h2 class="title sectiontitle">How probes and sensors work together</h2> <p class="p">The MID Server launches probes to collect information about a device. The probe sends back information to the sensor to be processed. If the probe has a post-processing script defined, the post-processing script does some data processing on the MID Server before data is sent back to the sensor on the ServiceNow instance. Otherwise the probes sends back all the data collected and the sensor performs this data processing. In both cases, the sensor updates the CMDB.</p> <p class="p">A multi-probe is a probe that contains probes. A multi-sensor processes the data from a multi-probe. To process the data from the multi-probe, the multi-sensor contains individual scripts to process the data returned by each probe contained in the Multiprobe, as well as a main multi-sensor script. The individual scripts pass their processed data to the main multi-sensor script.</p> <div class="fig fignone" id="c_DiscoveryProbesAndSensors__fig_v4f_p3b_cr"> <img class="image" id="c_DiscoveryProbesAndSensors__image_z2q_n2q_jz" src="../image/MultisensorExample.png" alt="The MultiSensor form" /> </div> </div> <div class="section"><h2 class="title sectiontitle">Probe types</h2> <div class="tablenoborder"><table cellpadding="4" cellspacing="0" summary="" id="c_DiscoveryProbesAndSensors__table_ixz_r1l_z4" class="table" frame="border" border="1" rules="all"><colgroup><col /><col /></colgroup><thead class="thead" style="text-align:left;"><tr class="row"><th class="entry cellrowborder" style="vertical-align:top;" id="d436384e211">Device</th><th class="entry cellrowborder" style="vertical-align:top;" id="d436384e214">Probe Type</th></tr></thead><tbody class="tbody"><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 "><p class="p"><span class="ph">Windows</span></p> computers and servers</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">Remote WMI queries, shell commands</td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 "><p class="p"><span class="ph">UNIX</span> and <span class="ph">Linux</span> servers</p> </td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 "><p class="p">Shell command (via SSH protocol, version 2). <span class="ph">Discovery</span> supports any Bourne-compatible shell.</p> </td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 ">Storage</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">CIM/WBEM queries</td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 ">Printers</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">SNMP queries</td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 ">Network gear (switches, routers, etc.)</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">SNMP queries</td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 ">Web servers</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">HTTP header examination</td></tr><tr class="row"><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e211 ">Uninterruptible Power Supplies (UPS)</td><td class="entry cellrowborder" style="vertical-align:top;" headers="d436384e214 ">SNMP queries</td></tr></tbody></table> </div> </div> </div> <div class="related-links"> <ul class="ullinks"><li class="link ulchildlink"><strong><a href="../../../product/discovery/reference/r_ListOfDiscoveryProbes.html">List of Discovery probes</a></strong><br /> A wide variety of probes exist for the Discovery application to detect elements on your network.</li><li class="link ulchildlink"><strong><a href="../../../product/discovery/reference/r_Sensors.html">Discovery sensors</a></strong><br /> <span class="ph">Every probe in Discovery must have a corresponding sensor to process the data returned.</span></li><li class="link ulchildlink"><strong><a href="../../../product/discovery/reference/r_Probes.html">Discovery probe management</a></strong><br /> <span class="ph">Several discovery probes and their associated sensors are included with Discovery. You rarely need to modify probes or sensors. But you might need to set parameters to control the behavior of a particular probe or align versions of customized probes.</span></li><li class="link ulchildlink"><strong><a href="../../../product/discovery/task/t_AlignVerCustProbeSens.html">Align versions of customized probes and sensors</a></strong><br /> If you customized a probe or sensor and upgraded to a new version of an instance, you need to realign the versions of the customized probe and sensor to the most current version.</li><li class="link ulchildlink"><strong><a href="../../../product/discovery/reference/r_MultiprobesIncludedWithDiscovery.html">Discovery multiprobes and multisensors</a></strong><br /> Multiprobes contain one or more simple probes configured to extract specific information from manageable devices by executing multiple queries with a single authentication.</li><li class="link ulchildlink"><strong><a href="../../../script/server-scripting/task/t_CustomProbeTextFile.html">Example custom Discovery probe and sensor: populate a CI with text file values</a></strong><br /> This custom <span class="ph">Discovery</span> probe helps you if you need to read a text file from a <span class="ph">Windows</span> computer and populate a CI in the CMDB with the values from the file.</li></ul> <div class="familylinks"> <div class="parentlink"><strong>Parent Topic:</strong> <a class="link" href="../../../product/discovery/reference/r-discovery.html" title="ServiceNow Cloud Discovery finds applications and devices on your network, and then updates the Multisource CMDB with the information it finds.">Discovery</a></div> </div> </div></body></html></div>