TCP connection discovery

  • Release version: Australia
  • Updated March 12, 2026
  • 4 minutes to read
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    Summary of TCP Connection Discovery

    TCP Connection Discovery enables the identification and classification of TCP connections using ADM and ADME probes, populating data in the TCP Connections[cmdbtcp]table. This process helps organizations maintain accurate visibility into their network connections and running processes.

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    Key Features

    • Connection Data: Tracks TCP connections including process ID (PID), IP address, port number, and connection type (listening or connecting).
    • Process Tracking: Monitors active processes and their connection states, recording details such as command paths and parent processes in the [cmdbrunningprocess] table.
    • Standard and Enhanced Probes: Supports both standard ADM probes for various operating systems and enhanced probes that provide additional functionality for continuous TCP-based discovery.
    • Key Parameters: Allows configuration of parameters such as the maximum result size for TCP tracking to optimize performance and prevent errors.

    Key Outcomes

    By utilizing TCP Connection Discovery, ServiceNow customers can achieve:

    • Accurate mapping of application dependencies through detailed TCP connection data.
    • Improved network monitoring and management capabilities by identifying active processes and their connections.
    • Enhanced performance and error management through configurable parameters for both standard and enhanced ADM probes.

    Discovery identifies and classifies information about TCP connections using the ADM and ADME probes.

    Discovery populates this data in the TCP Connections [cmdb_tcp] table.

    Label Table Name Field Name Description
    Absent cmdb_tcp absent If the process is no longer running on this device. The first time the process is detected, the value is not selected (meaning that it is not absent). If Discovery runs again and does not detect the process, it is selected.
    Computer cmdb_tcp computer The device that is connected to or is listening on the TCP port.
    IP cmdb_tcp ip The IP address that this device or process is listening on or is connected to. If the IP address is 127.0.0.1, it is the host computer itself.
    PID cmdb_tcp pid The ID of the process that is connecting to or listening on this device (IP address).
    Port cmdb_tcp port The port number through which TCP traffic was detected.
    Process cmdb_tcp process The process that is connecting to or listening on the port.
    Type cmdb_tcp type
    • Listening on: the process is listening to the device via TCP.
    • Connecting to: if the process is connected to this device via TCP.
    count cmdb_tcp count The number of times that Discovery detects a specific TCP connection. This field is used by ADM enhanced probes.

    Discovery populates this data in the Running Process [cmdb_running_process] table.

    Label Field Name Description
    Name name The name of the running process.
    Computer computer The device that the process is running on.
    Parent parent The parent process of this process, if any.
    Listening on listening_on The ports that the processes is listening on.
    Connected to connected_to The ports that the processes is connected to.
    Command command The command for this process, including the path.
    PID pid The ID for the process.
    PPID ppid The ID for the parent process.
    Absent absent If the process is no longer running on this device. The first time the process is detected, the value is not selected (meaning that it is not absent). If Discovery runs again and does not detect the process, it is selected.
    Classify classify If the running process should be classified.
    Key parameters key_parameters The key parameters for the command.
    Parameters parameters The parameters for the command.
    Count count The number of times that Discovery detects a specific TCP connection. This field is used by ADM enhanced probes.

    Standard ADM probes

    Discovery launches these probes with standard ADM discovery:
    Name Description Includes these sub-probes
    AIX - ADM Queries for information about active (running) AIX processes and active connections - the information required to perform application dependency mapping.
    • AIX - Active Connections
    • AIX - Active Processes
    HP-UX - ADM Queries for information about active (running) HP-UX processes and active connections - the information required to perform application dependency mapping.

    This probe requires that lsof be installed and the UNIX - Active Connections probe be activated, which is inactive by default.
    • UNIX - Active Connections
    • HP-UX - Active Processes
    Solaris - ADM Queries for information about active (running) Solaris processes and active connections - the information required to perform application dependency mapping. This probe is triggered by the Solaris Zones probe. The system triggers an ADM probe for each local zone contained in a global zone.

    This probe requires that lsof be installed on the global zone.
    • Solaris - Active Processes
    • Solaris - Active Connections
    UNIX - ADM Queries for information about active (running) UNIX processes and active connections - the information required to perform application dependency mapping.
    • UNIX - Active Connections
    • UNIX - Active Processes
    Windows - ADM Queries for information about active (running) Windows processes and active connections - the information required to perform application dependency mapping.
    • Windows - Active Connections
    • Windows - Active Processes
    UNIX - ADM netstat Performs the same functions as the UNIX ADM probe relying on netstat to support continuous TCP-based discovery. Service Mapping uses this probe for traffic-based discovery.
    • UNIX - Active Connections with Netstat. This probe retrieves TCP connections to populate the cmdb_tcp and cmdb_tcp_connection tables.
    • UNIX - Active Processes. This probe retrieves TCP processes and populates the cmdb_running_process table.

    Enhanced ADM probes

    Discovery launches these probes when enhanced ADM is activated:
    Probe Description
    Windows - ADM Enhanced Performs the same functions as the Windows ADM probe with additional parameters to control continuous TCP-based discovery. This probe is compatible with WinRM and non-WinRM supported MID Servers. Configure your MID Server using the mid.windows.management_protocol parameter. See MID Server parameters for the values you can use for this parameter.
    UNIX - ADM Enhanced Performs the same functions as the UNIX ADM probe with additional parameters to control continuous TCP-based discovery.
    Use these probe parameters with the enhanced ADM probes:
    Parameter Description
    mid.adme.max_result_size Control the size of the TCP tracking file.
    max.adme_result_payload_size Controls the size of the result, including the payload.
    Note:
    If this is greater than the MID Server properties mid.discovery.max_payload_size, a configuration error can occur.