The SNMP Query operation on a pattern for a custom device query allows Discovery to retrieve

information from the target device using the SNMP protocol. It is best practice to use the published

manufacturer’s device MIB, which is the official and standard definition of the device’s SNMP data.

Using the manufacturer’s device MIB ensures that the query is accurate, consistent, and compatible

with the device. Modifying the default MIB information, enabling SSH as a secondary protocol, or

using live devices in production are not recommended practices, as they may introduce errors,

security risks, or performance issues123.

Reference:

SNMP Query pattern operation - Product Documentation: San Diego - Now Support Portal

Load a MIB file - Product Documentation: Vancouver - ServiceNow

How Loading of MIB file works on SNMP Browser ( Pattern Step - SNMP Query) - Support and

Troubleshooting

A classifier is a set of rules that identifies a device type based on the results of a probe. A classifier

can have one or more related lists that define the classification criteria, the pattern probes, and the

triggers probes. The pattern probes related list specifies which horizontal discovery pattern to run for

the device type. The triggers probes related list specifies which probes to run after the device is

classified, and before the horizontal discovery pattern is executed. The triggers probes can be used to

gather additional information or credentials that are needed for the horizontal discovery pattern12.

Reference:

1: ServiceNow Discovery Overview, page 9

2: ServiceNow Discovery Documentation, Classifiers section

Discovery Range Sets in ServiceNow Discovery offer a flexible way to manage and identify networks.

They simplify the administration of network discovery by allowing administrators to define groups of

IP ranges. This organization helps in effectively managing and targeting different network segments

without needing to define each IP range in individual Discovery Schedules. Range Sets do not

necessarily show the number of IPs in a subnet, nor are they the only way to define multiple IP

ranges in a schedule.

In ServiceNow Discovery, relationships between Configuration Items (CIs) in a horizontal pattern are

created using the "Create Relation/Reference" operation. This operation allows the pattern to define

and establish relationships or

between discovered CIs, based on the information gathered

during the discovery process. Options B and C are incorrect as relationships are not automatically

created nor is it true that they cannot be created via patterns. Option D, "Create Connections," is not

a standard operation in this context. Reference = ServiceNow Discovery documentation, specifically

the sections on creating and managing horizontal discovery patterns.

A horizontal discovery pattern is a set of steps that execute operations to identify, classify, and

populate attributes for configuration items (CIs) of a specific category or class, such as infrastructure

or application. A horizontal pattern can be applied to any operating system or platform that supports

the required protocols and commands12.

Reference:

Horizontal discovery patterns

Discovery pattern types

A MID Server needs to have access to the install.service-now.com domain to automatically stay up-

to-date with instance versions. This domain hosts the MID Server upgrade files that are downloaded

and installed by the MID Server when a new version is available. The MID Server checks for updates

every 24 hours by default, or when the mid.upgrade.check_interval property is set12.

Reference:

1: ServiceNow Discovery Documentation, MID Server Upgrade section

2: ServiceNow Support Article, Connections to allow list for the MID Server

The default thread count for a MID Server is 25. This means that the MID Server can run up to 25

worker threads simultaneously to execute the jobs assigned to it by the ServiceNow instance. The

worker threads are divided into different thread pools based on the priority of the jobs. The MID

Server can also adjust the thread count dynamically based on the system resources and the

workload. The thread count can be configured by changing the MID Server parameters in the

ServiceNow instance12. Reference = 1: MID Server Max Threads - Worker Groups - Priority and

Queues - ServiceNow 2: Product Documentation | ServiceNow

The Discovery Dashboard provides a summary of the Discovery status, including the number of active

discovery errors, the number of devices discovered, and the number of credentials used. Each error

has a help link that provides more information about the cause and possible solutions.

Reference:

Discovery Dashboard

Discovery troubleshooting | Error messages

The Extension section in a horizontal pattern is executed after the Identification sections have

completed and the CI has been identified. The Extension section allows adding additional attributes

or relationships to the CI, or launching other patterns for further discovery12.

Reference:

1: ITOM: Extending Discovery/Service Mapping Patterns - GlideFast ServiceNow

2: Horizontal Pattern probe - Product Documentation: San Diego - ServiceNow

The Credential Affinity table is a table that associates an IP address and a credential in Discovery1. It

is used to store the credential that was successfully used to access a device during Discovery2. It can

also be used to manually assign a credential to an IP address or a range of IP addresses3. The other

options are not tables that associate an IP address and a credential in Discovery. The Service Affinity

table is a table that associates a business service and a credential. The Service CI Association table is

a table that associates a business service and a configuration item (CI). The Tags table is a table that

stores tags that can be applied to records in any table.

Reference: 1: Credential Affinity table 2: Credential affinity 3: Manually assign a credential to an IP

address : Service Affinity table : Service CI Association table : Tags table