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Configure Shazzam probe parameters and payload size

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Configure Shazzam probe parameters and payload size

When you run Discovery, the Shazzam probe finds your active network devices by scanning specified ports on specified IP address ranges. If the list of IP ranges being scanned is very large, you can configure the Shazzam payload for JSON encoding to reduce its size.

Before you begin

Role required: admin

About this task

You control the behavior of individual Shazzam probes using basic and advanced parameters.

For instructions on configuring probe parameters, see Set probe parameters.

Procedure

  1. Navigate to Discovery Definition > Probes.
  2. Select Shazzam.
  3. Add or edit parameters in the Probe Parameters related list.
  4. Configure the basic Shazzam parameter.
    These parameters are defined in the config.xml file on the MID Server, but you can edit the values in the Shazzam probe record as well. Changes to specific parameters that could disconnect you from the MID Server are prohibited in the probe record and can only be made in the configuration file.
    Table 1. Basic Shazzam parameters
    Parameter Description
    shazzam_chunk_size Maximum number of IP addresses Shazzam will scan in parallel. This parameter primarily controls outbound port consumption.

    Default: 100

    regulator_max_packets Sets the number of packets that Shazzam can launch in the time interval specified by the regulator_period_ms parameter.

    Default: 1

    regulator_period_ms Sets the interval, in milliseconds, in which Shazzam can launch packets.

    Default: 1

  5. Configure the advanced Shazzam parameters.
    These parameters are available for fine tuning the Shazzam probe. These values are defined in the probe record only.
    Table 2. Shazzam advanced parameters
    Parameter Description
    BannerTCP_waitForConnectMS Sets the number of milliseconds the BannerTCP scanner waits for a connection and banner.

    Default: 1500

    debug Enables debug logging if set to true.

    Default: false

    delay_webem Delays classification of systems with a WBEM port open until the final Shazzam sensor job. In the case of a large schedule discovering many WBEM ports, delaying classification until the last sensor job could cause the node to run out of memory. Setting this parameter to false allows classification of these systems to occur across all Shazzam sensor jobs.

    Default: true

    DNS_alternativePort Deprecated
    DNS_waitForResponseMS Sets the number of milliseconds the DNS scanner waits for a response.

    Default: 1000

    GenericTCP_waitForConnectMS Sets the number of milliseconds the GenericTCP scanner waits for a connection.

    Default: 1000

    HTTP_waitForConnectMS Sets the number of milliseconds the HTTP scanner waits for a connection.

    Default: 500

    HTTP_waitForResponseMS Sets the number of milliseconds the HTTP scanner waits for a response.

    Default: 500

    NBT_alternativePort Deprecated
    NBT_waitForResponseMS Sets the number of milliseconds the NBT scanner waits for a response.

    Default: 500

    report_inactive When true, reports device that are alive but inactive. For example, a device has no ports open but refuses at least one port connection request.

    Default: true

    scanner_log Enables scanner logging if set to true. This logging information appears in the Shazzam probe response.

    Default: false

    shazzam_report_dead When true, reports devices with dead IP addresses. For example, a device that has all ports closed.

    Default: false

    SNMP_alternativePort Deprecated
    SNMP_tapIntervalMS Sets the number of milliseconds the SNMP scanner waits between taps.

    Default: 1000

    SNMP_taps Sets the number of taps (requests) the SNMP scanner attempts.

    Default: 2

    SNMP_waitForResponseMS Sets the number of milliseconds the SNMP scanner waits for a response after the last tap.

    Default: 1000

Control Shazzam payload size

A system property converts Shazzam payloads into JSON strings, which dramatically reduces their size. This setting prevents nodes from running out of memory when a single schedule discovers large numbers of IP ranges.

Before you begin

Role required: admin

About this task

The glide.discovery.shazzam_ranges_json property is set to true for new instances. This setting encodes the payload as a JSON string. The property is configurable by administrators and is available in the Discovery Definition > Properties module. The property label is Use JSON for IP ranges in Shazzam in the module.

This property is set to false in upgraded instances and is not visible by default. Adding the property manually to your upgraded instance enables the feature, but does not add it to the Discovery Definition > Properties module. To enable JSON encoding and add it to the module, import the update set attached to KB0687626.

To enable JSON coding manually for upgraded instances:

Procedure

  1. In the navigation filter, type sys_properties.list and press Enter.
  2. In the list of system properties, click New.
  3. Complete the form, using these field values:
    • Name: glide.discovery.shazzam_ranges_json
    • Description: Encodes the Shazzam payload in JSON.
    • Value: true
  4. Click Submit.
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