The process of developing and managing Azure Sentinel Information Model (ASIM) parsers is critical in preparing for the SC-200 Microsoft Security Operations Analyst exam. This article will delve deep into this topic by explaining what ASIM parsers are, their importance in Azure Sentinel, and outlining a step-by-step guide on how you can develop and manage them effectively.
1. Understanding ASIM Parsers
ASIM parsers are instrumental in Azure Sentinel, where they enhance the observability, alert efficiency, and exploration of event data. These parsers normalize the ingest logs in Azure Monitor Log Analytics and Azure Sentinel, making it easier to come up with uniform analytic rules that work across various platforms and environments.
Azure Sentinel has a prefabricated set of normalization schemas for common event types such as Process, Network, DNS, URL, and many more.
2. Developing ASIM Parsers
Developing an ASIM parser involves a few steps:
- a. Identify the Schema: First, you need to identify which type of event the parser is going to handle. Azure Sentinel provides numerous predefined schemas for common data sources. For instance, if you’re handling Network events, you would have to work with NetworkEvent schema.
- b. Define Parser Function: Next, implement a parser function in Kusto Query Language (KQL) using the parse or parsejson operators. The schema you identified in Step 1 guides you in identifying which fields require extraction. Here’s a simple KQL function sample:
let MyParser=(rawEvent: string)
{
parse rawEvent with * 'ProcessName="' ProcessName:string '",' *
}
This function will extract the value of ProcessName from the raw event log.
- c. Validate Function: Finally, you’d need to validate your function by running some raw logs through it and confirm that it correctly extracts all the required fields.
3. Managing ASIM Parsers
After developing ASIM parsers, you should manage them properly to assure their effective operation. That entails updating them regularly to handle changes in schema or event logs format and monitoring their performance to ensure they work as expected.
4. Importance of ASIM Parsers in Passing the SC-200 Exam
Developing and managing ASIM parsers is crucial for anyone preparing to take the SC-200 Microsoft Security Operations Analyst exam. This exam requires a deep understanding of how to implement threat protection technologies, including Azure Sentinel and Azure Defender to secure your organization. From the exam perspective, you are expected to know how to write and manage parsers, normalize data from various sources, and how this contributes significantly to threat hunting and incident response.
In summary, ASIM parsers play a pivotal role in making Azure Sentinel a robust and adaptable SIEM solution. Therefore, understanding how to develop and manage them is indispensable for anyone looking to take the SC-200 Microsoft Security Operations Analyst exam.
Practice Test
True/False: ASIM is a special type of data parser created by Microsoft to parse security data in Azure.
- True
- False
Answer: True.
Explanation: ASIM (Azure Security Information Model) performs normalization and integration tasks for the data ingested in Azure Sentinel, which allows you to manage and correlate security data efficiently.
Which of the following is a key function of ASIM parsers?
- A. Improve database capacity
- B. Reduce data redundancy
- C. Normalize data schema
- D. Enhance data visualization
Answer: C. Normalize data schema
Explanation: ASIM parsers play a crucial role in normalizing data schemas, which allows for efficient correlation and analysis of security data in Azure Sentinel.
True/False: ASIM parsers have nothing to do with schema mapping in Azure Sentinel.
- True
- False
Answer: False.
Explanation: ASIM parsers indeed play a vital role in schema mapping, as they help to normalize data schemas from diverse data sources, ensuring they adhere to a single, unified format that Azure Sentinel can interpret.
Which of the following would you use to develop and test ASIM parsers?
- A. Azure DevOps
- B. Azure Notebooks
- C. Log Analytics
- D. Azure Functions
Answer: B. Azure Notebooks
Explanation: Azure Notebooks is typically used to develop and test ASIM parsers because it offers an interactive coding environment for creating and running code snippets.
True/False: Azure Sentinel provides out-of-the-box ASIM parsers for a variety of security data types.
- True
- False
Answer: True.
Explanation: Azure Sentinel provides readily available ASIM parsers for several common security data types that you can utilize for your security data analysis.
In Azure Sentinel, ASIM parsers play an important role in:
- A. Code optimization
- B. Traffic balancing
- C. Data normalization
- D. Storage management
Answer: C. Data normalization
Explanation: ASIM parsers in Azure Sentinel are primarily responsible for data normalization, which ensures that data from various sources is compatible with Azure Sentinel.
True/False: You can use Log Analytics to view and query the output of an ASIM Parser.
- True
- False
Answer: True.
Explanation: Azure’s Log Analytics is a tool that you can use to monitor and diagnose issues and perform ad-hoc queries on the parsed ASIM data.
Which of the following is a basic requirement when creating a custom ASIM parser in Azure Sentinel?
- A. The data source should not have a corresponding built-in ASIM parser
- B. The data source must be continuously updated
- C. The data source should have an API for connectivity
- D. All of the above
Answer: A. The data source should not have a corresponding built-in ASIM parser
Explanation: You usually create a custom ASIM parser when the data source you need to parse does not have a corresponding built-in ASIM parser in Azure Sentinel.
True/False: An improperly configured ASIM parser can affect the performance of Azure Sentinel.
- True
- False
Answer: True.
Explanation: An incorrectly configured ASIM parser can cause inefficient data mapping, slow queries, and other performance issues in Azure Sentinel.
None of the built-in ASIM-parsers suit your needs. What can you do?
- A. Build your own ASIM-parsers.
- B. Download third-party parsers.
- C. Adjust the built-in parsers.
- D. All of the above.
Answer: D. All of the above.
Explanation: Azure Sentinel allows you to create your own ASIM parsers, adjust the built-in ones, or import parsers from third-party sources if none of the built-in parsers fit your needs.
Interview Questions
What is ASIM parsing?
ASIM, which stands for Azure Security Information Model, is a method used in Azure Sentinel for normalizing and aggregating data into a common schema. Parsing refers to the process of breaking down and interpreting the data.
What are the main uses of ASIM parsers in Azure Sentinel?
ASIM parsers are used in Azure Sentinel to align and normalize data, which helps with correlations, investigations, and threat detections across multiple data sources.
Can you create custom ASIM parsers in Azure Sentinel?
Yes, while Azure Sentinel provides built-in ASIM parsers for common log types, you do have the ability to create custom ASIM parsers for any proprietary or unsupported log types.
What type of data can ASIM parsers handle?
ASIM parsers can handle any structured log data. This includes data available in CSV, JSON, Key-Value, or any other structured format.
How do ASIM parsers aid in log management in Azure Sentinel?
ASIM parsers enable Azure Sentinel to deal with multiple log source types and structures by extracting, transforming, and loading the relevant log data into a unified schema for easier querying and analysis.
What is the main objective of the ASIM normalization process in Azure Sentinel?
The work of normalizing data with ASIM is meant to aid analysts in easily correlating events across diverse datasets, enhancing the security analysis and threat detection processes.
What Azure services does Sentinel integrate with for ASIM parsing?
Azure Sentinel integrates with Azure Log Analytics for ASIM parsing. Log Analytics Workspace serves as the storage and querying engine behind Azure Sentinel.
Can third-party data be parsed by using ASIM in Azure Sentinel?
Yes, Azure Sentinel allows for the ingestion of third-party data, which can then be parsed by using ASIM.
How do you improve query efficiency with ASIM parsers?
By transforming diverse data schemas to a unified schema during the ASIM parsing process, your query efficiency can be significantly optimized.
How does ASIM in Azure Sentinel integrate with KQL?
Once data has been normalized by ASIM, it can be queried using Kusto Query Language (KQL), a read-only request to process data and return results.
What are the steps to develop a custom parser in Azure Sentinel?
In Azure Sentinel, a custom parser can be created by writing a Kusto Function that uses the parse or extract keyword to define a new log format.
Can ASIM parsers be used for real-time monitoring in Azure Sentinel?
Yes, once logs have been normalized with ASIM parsers, they can be used in real-time monitoring dashboards in Azure Sentinel.
What are the limitations of the built-in ASIM parsers in Azure Sentinel?
The built-in ASIM parsers can only support certain pre-defined log formats. If your data formats are not supported out-of-the-box, you will need to create a custom parser.
How does ASIM help in threat hunting?
By transforming different schemas into a unified format, ASIM simplifies and accelerates the threat-hunting process since security analysts can search across multiple log sources without having to understand the individual log formats.
Can you update ASIM parsers in Azure Sentinel?
Yes, Azure Sentinel provides the ability to update the existing ASIM parsers to adjust the parsing rules according to your needs.