Discovery

ServiceNow Interview Questions

Discovery

 

1. What is ServiceNow Discovery and how does it work?

ServiceNow Discovery is a tool that helps organizations automatically identify and inventory their IT assets and infrastructure. It works by scanning the network to find devices and applications, classifying them, and populating the Configuration Management Database (CMDB) with the discovered data.

 

2.    What is the purpose of ServiceNow Discovery?

The purpose of ServiceNow Discovery is to automatically identify and inventory IT assets and infrastructure within an organization. It populates the Configuration Management Database (CMDB) with accurate and up-to-date information about devices, applications, and their relationships.

 

3.    What are the key components of ServiceNow Discovery?

The key components of ServiceNow Discovery include:

1. MID Server: Facilitates communication between ServiceNow and external systems.
2. Probes and Sensors: Collect and process data from discovered devices.
3. Discovery Patterns: Define the steps and logic for identifying and exploring devices.
4. Discovery Schedules: Define when and where Discovery scans are performed.

 

4.    Describe the phases of the Discovery process.

The Discovery process involves several phases:

1. Scanning: Identifies active IP addresses and determines which ports are open.
2. Classification: Determines the type of device or operating system based on open ports.
3. Identification: Matches discovered items to existing Configuration Items (CIs) in the CMDB.
4. Exploration: Collects more detailed information about the discovered devices or applications.
5. Dependency Mapping: Determines relationships between CIs, providing insight into how systems interact.

 

5. What is a MID Server and how is it used in Discovery?

A MID Server (Management, Instrumentation, and Discovery Server) is a Java application that runs on a server within your network. It facilitates communication between ServiceNow and external systems, especially those behind firewalls. It is used in Discovery to execute probes and sensors, gather data, and return the results to ServiceNow.

 

6. How do you configure and maintain Discovery schedules?

Discovery schedules are configured in ServiceNow by navigating to Discovery Schedules and creating a new schedule. You can specify the IP ranges, frequency, and time of the scans. Maintenance involves regularly reviewing and updating the schedules to ensure they cover all necessary network segments and adjusting them based on network changes.

 

7. What are the types of Discovery in ServiceNow?

There are two main types of Discovery in ServiceNow:

1. Horizontal Discovery: Finds devices and applications and populates them in the CMDB.
2. Top-Down Discovery (Service Mapping): Maps business services to identify how applications and infrastructure work together.

 

8. How do you troubleshoot Discovery issues?

Troubleshooting Discovery issues involves several steps:

1. Check Logs: Review Discovery logs and MID Server logs for errors.
2. Verify Credentials: Ensure that the credentials used for Discovery are correct and have the necessary permissions.
3. Network Configuration: Verify network configurations, such as firewalls and IP ranges.
4. Test Probes and Sensors: Manually test probes and sensors to ensure they are working correctly.
5. Review Patterns: Check Discovery patterns for any misconfigurations or errors.

 

9. What is the ECC Queue and what role does it play in Discovery?

The ECC (External Communication Channel) Queue is a table in ServiceNow that stores messages sent to and received from MID Servers. It plays a crucial role in Discovery by managing the communication between ServiceNow and the MID Servers, ensuring that data is collected and processed correctly.

 

10. How do you handle network changes and updates in Discovery?

Handling network changes and updates in Discovery involves:

1. Updating IP Ranges: Adjusting Discovery schedules to include new or changed IP ranges.
2. Reconfiguring MID Servers: Ensuring MID Servers are correctly configured to access new network segments.
3. Credential Updates: Updating credentials if there are changes in authentication methods or permissions.
4. Testing: Performing test scans to verify that the changes are correctly reflected in the Discovery results.

 

11. What are Discovery Patterns and how are they used?

Discovery Patterns are templates that define the steps and logic used to identify and explore devices and applications during the Discovery process. They are used to customize and extend Discovery to handle specific types of devices and applications, ensuring accurate and comprehensive data collection.

 

12. How do you optimize Discovery performance and scalability?

Optimizing Discovery performance and scalability involves:

1. Efficient Scheduling: Configuring Discovery schedules to avoid overlapping scans and reduce network load.
2. MID Server Load Balancing: Distributing the load across multiple MID Servers to improve performance.
3. Pattern Optimization: Streamlining Discovery patterns to minimize unnecessary steps and reduce processing time.
4. Regular Maintenance: Regularly reviewing and updating configurations to ensure optimal performance

 

13. How do you handle credentials in ServiceNow Discovery?

Credentials in ServiceNow Discovery are managed through the Credentials module. You can create and store credentials for different types of devices and applications. During the Discovery process, these credentials are used to authenticate and access the devices being discovered.

 

14. What are the common challenges faced during ServiceNow Discovery, and how do you address them?

Common challenges include network configuration issues, credential problems, and incomplete data collection. These can be addressed by:

                                               i.     Ensuring correct network configurations and IP ranges.

                                              ii.     Verifying and updating credentials.

                                             iii.     Reviewing and optimizing Discovery patterns and schedules.

                                            iv.     Regularly monitoring and troubleshooting Discovery logs.

 

15. How do you ensure data accuracy in the CMDB using Discovery?

                                        i.         To ensure data accuracy in the CMDB using Discovery:

                                       ii.         Regularly run Discovery scans to keep data up-to-date.

                                      iii.         Use accurate and comprehensive Discovery patterns.

                                     iv.         Implement validation rules and data quality checks.

                                       v.         Monitor and resolve any discrepancies or errors in the Discovery process.