---
sourceDocument: Xanadu IT Operations Management
sourceDocumentLink: https://www.servicenow.com/docs/r/xanadu/it-operations-management

 Release :

    - xanadu

ft:locale :

    - en-US

ft:publication_title :

    - Xanadu IT Operations Management

ft:clusterId :

    - itom

bundleId :

    - itom

workflow :

    - Technology


---

# File-based Discovery

# File-based Discovery {#ariaid-title1}

* Release version: Xanadu
* 
* Updated August 1, 2024
* 
* ![](https://www.servicenow.com/docs/portal-asset/ico-clock) 3 minutes to read

File-based Discovery helps you
identify what software is running on your Windows and UNIX servers and devices, even if there is no
registration information available. You can then manage and maintain records of your software
licenses, check for unlicensed files, detect forbidden or damaged files, and help evaluate any
threats from unwanted files.

## Required plugins {#file-based-discovery__section_cys_3jr_13b}

The File-based Discovery \[com.snc.discovery.file_based_discovery\] plugin is required for file signature filtering. Your Discovery subscription includes this plugin, but you must [request activation](https://www.servicenow.com/docs/access?context=t_RequestAPlugin&version=xanadu&pubname=xanadu-platform-administration&ft:locale=en-US). Once the File-based Discovery plugin is active, the Software Asset Management - File Signature Normalization \[com.snc.file_signature_normalization\] plugin is also activated. For more information on the File Signature Normalization plugin, see [File Signature Normalization](https://www.servicenow.com/docs/access?context=sam-file-based-discovery&version=xanadu&pubname=xanadu-it-asset-management&ft:locale=en-US).

## How File-based Discovery
works {#file-based-discovery__section_ifz_rbp_x2b}

File-based Discovery enhances the
pre-existing discovery of installed software. It scans target servers for a known list of file
signatures and processes those files with an established set of rules. The resulting data
enhances the identification of installed software and identifies unregistered software
products.

File-based Discovery is triggered in the exploration phase of normal Discovery. File-based Discovery probes execute a scan searching for
specific file extensions or file names in paths that you configure. The resulting file
information is returned in the probe payload. The sensor attempts to match the discovered files
with installed software, using the file name, size, and version returned by the probe.
File-based Discovery uses file signatures to detect software that might not have
been registered. This information is then stored in the File Information \[cmdb_file_information\]
table with a reference to the CI of the server. You can view the files found from each CI in a
related list on this table. For more information, see [Related list of CI components](https://www.servicenow.com/docs/access?context=r_RelatedListsOfCIComponents&version=xanadu&pubname=xanadu-servicenow-platform&ft:locale=en-US) When [Software Asset Management](https://www.servicenow.com/docs/access?context=c_SoftwareAssetMgmt&version=xanadu&pubname=xanadu-it-asset-management&ft:locale=en-US) (SAM) is active, if any file matches a software product, Discovery populates the Product and Publisher information for that file. Use this
information to understand what software is running on your server and to help evaluate any
threats from unwanted files. Discovery uses lists of known file signatures for
Windows and UNIX to constrain the scope of the search. The
filtering process for Windows and UNIX hosts is executed differently because
their signature lists differ greatly in size. The much smaller UNIX signature
list is included with the Unix - File Discovery probe and processed directly on the target. The
Windows signature list is much larger and cannot be processed on the target. The Windows - File
Discovery probe scans the target for specific file extensions and paths and returns these
results to the MID Server. The MID Server performs file signature
filtering using the entire Windows list. The MID Server then sends all file
information back to the instance for normalization and matching.

If SAMP is active on the instance, File-based Discovery creates or updates
identified software products in the Software Installation \[cmdb_sam_sw_install\] table and
updates the licenses of matched software packages. Without SAMP, no software records are created
and only the file information goes into the File Information \[cmdb_file_information\] table.  
You can enable SWID tags in the Discovery Configuration Console. With SWID tag enabled, when running File-based Discovery, the SWID tag information then populates the \[cmdb_swid_tag\] table. Information about the software installed on a particular machine includes name, file information, publisher, version, installed on, and content. The software_installation column in the \[cmdb_swid_tag\] is a reference to the \[cmdb_sam_sw_install\] table.  
Note:  
Base64 package is a prerequisite for any UNIX or Linux servers to scan SWID tag files using File-based Discovery.
Figure 1. File-based Discovery filtering flow  
File-based Discovery inserts any file not matched by the normalization process into the Unidentified File Set \[cmdb_unidentified_file_set\] table. You can update the records in this table and provide additional details for previously unidentified files. If you provide values for the Product and Publisher fields for a file, settings in SAMP can enable File-based Discovery to use that file for installed software matching in future discoveries.  
Note:  
You can disable File-based Discovery at any time by changing the setting in the [Discovery Configuration Console](https://www.servicenow.com/docs/~6xqihAvmK05xJ2qyr4zFg#c_DiscoveryConfigurationConsole "Use the Discovery Configuration Console to manage what kind of CIs and CI information you want to discover."). If you disable File-based Discovery before scan results are returned, the file data is ignored.  
Figure 2. File-based Discovery table schema Note:  
File-based Discovery supports Windows and UNIX devices. The UNIX probe is POSIX-compliant and should run on any Linux/Solaris server. We support Windows versions 2008, 2008R2, 2012R2, 2016, 2019, and above with PowerShell 3.0 to 5.1. We also support AIX versions 5.3, 6.1, and 7.1 and HP/UX 8.11.

If you are running File-based Discovery on Ubuntu version 20, modify the
default Bourne shell (sh) to point to Bourne Again shell (bash).

Version information is populated only for the files with version information returned from
probes. Not all files will have versions. Files with extensions such as exe, jar, etc, will
have versions.  
![File-based Discovery reference information link]()

