Splunk – Types of Command

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Splunk is a popular software platform used for searching, analyzing, and visualizing machine-generated data in real-time. Splunk commands are the building blocks of searches in Splunk. There are many types of Splunk commands, including:

  1. Search Commands: These commands are used to search for data in Splunk. Some examples of search commands include “search,” “where,” “eval,” and “stats.”
  2. Reporting Commands: These commands are used to generate reports based on search results. Some examples of reporting commands include “table,” “chart,” “stats,” and “timechart.”
  3. Transforming Commands: These commands are used to transform data in search results. Some examples of transforming commands include “rex,” “rename,” “fields,” and “replace.”
  4. Event Annotations Commands: These commands are used to add annotations to events in search results. Some examples of event annotations commands include “tags,” “addinfo,” and “lookup.”
  5. Filtering Commands: These commands are used to filter data in search results. Some examples of filtering commands include “search,” “where,” “dedup,” and “uniq.”
  6. Stats Commands: These commands are used to perform statistical analysis on search results. Some examples of stats commands include “count,” “sum,” “avg,” “max,” and “min.”
  7. Lookup Commands: These commands are used to enrich search results with data from external sources. Some examples of lookup commands include “lookup,” “inputlookup,” and “outputlookup.”

These are just some examples of the types of commands available in Splunk. There are many more commands and variations within each command category that can be used to analyze and visualize data in Splunk.

Streaming and non-streaming commands:

In Splunk, commands can be classified into two main categories: streaming and non-streaming commands.

  1. Streaming Commands: Streaming commands are executed as the data is being read from the input source. These commands can process data in real-time and do not require Splunk to read the entire dataset before they can be executed. Examples of streaming commands include “dedup,” “eval,” “fieldformat,” “rex,” and “search.”
  2. Non-Streaming Commands: Non-streaming commands are executed after the data has been read from the input source and indexed into Splunk. These commands require Splunk to read the entire dataset before they can be executed. Examples of non-streaming commands include “chart,” “join,” “stats,” “timechart,” and “transaction.”

The main difference between streaming and non-streaming commands is their execution time. Streaming commands are executed as the data is being read, which means they can process data in real-time and provide faster results. On the other hand, non-streaming commands are executed after the data has been indexed, which means they require more processing time and may take longer to execute.

When creating a search in Splunk, it’s important to consider which type of command to use based on the size of the dataset and the performance requirements of the search. Streaming commands are typically used for larger datasets and real-time analysis, while non-streaming commands are used for smaller datasets and more complex analysis.

Processing attributes:

In Splunk, processing attributes are metadata tags that can be added to search commands to modify the behavior of the search. These attributes can be used to change the search results, set options for how the search is executed, and modify the way that the search is displayed.

Some examples of processing attributes in Splunk include:

  1. field: This attribute specifies the fields that should be displayed in the search results. For example, | stats count by field will display the count of each unique value in the “field” field.
  2. where: This attribute is used to filter the data that is returned in the search results. For example, | where field="value" will only return events where the “field” field contains the value “value”.
  3. sort: This attribute is used to sort the search results. For example, | sort field will sort the search results in ascending order based on the “field” field.
  4. limit: This attribute is used to limit the number of search results returned. For example, | head 10 will only return the first 10 events in the search results.
  5. by: This attribute is used to group the search results based on one or more fields. For example, | stats count by field1, field2 will display the count of each unique combination of values in the “field1” and “field2” fields.
  6. dedup: This attribute is used to remove duplicate events from the search results. For example, | dedup field will remove events where the “field” field contains duplicate values.
  7. fillnull: This attribute is used to replace null values with a specified value. For example, | fillnull value="N/A" will replace null values with the string “N/A”.

These processing attributes can be used in combination with search commands to create powerful and flexible searches in Splunk.

Distributable streaming:

Distributable streaming is a feature in Splunk that allows a search to be divided and processed in parallel across multiple indexing peers or search heads. This feature is particularly useful when dealing with large amounts of data, as it allows for faster processing times and more efficient use of computing resources.

In distributable streaming, the search is divided into multiple tasks, with each task being processed independently on a separate Splunk instance. The results from each task are then combined to provide a single set of search results. Distributable streaming can be used with both streaming and non-streaming commands in Splunk.

To use distributable streaming in Splunk, you must have a distributed deployment with at least one search head and one or more indexing peers. The search head distributes the search across the indexing peers, and each indexing peer processes a portion of the search. The results are then returned to the search head, which combines them into a single set of results.

Distributable streaming is particularly useful when dealing with large datasets or when performing complex searches that require significant processing power. By distributing the search across multiple instances, you can reduce the processing time and improve the overall performance of the search.

To use distributable streaming, you must have the appropriate permissions and configurations set up in your Splunk deployment. You can also configure the search settings to control how the search is distributed and processed across the indexing peers.

Centralized streaming:

In Splunk, centralized streaming refers to a feature that allows you to stream data from one centralized location to multiple downstream Splunk instances. This can be useful in situations where you have a large amount of data that needs to be analyzed by multiple teams or applications.

With centralized streaming, you can configure a Splunk instance to act as a “forwarder,” which receives data from a source and then streams that data to one or more downstream Splunk instances. This can be done in real-time, which means that the downstream instances receive the data as soon as it is available.

Centralized streaming can be used to distribute data to multiple Splunk instances for a variety of purposes, such as load balancing, redundancy, and data analysis. For example, you may have multiple Splunk instances that are used by different teams to analyze the same data, or you may have multiple instances set up to provide redundancy and ensure that data is always available.

To use centralized streaming in Splunk, you must have a distributed deployment with at least one forwarder and one or more downstream Splunk instances. You can configure the forwarder to stream data to the downstream instances using various protocols, such as TCP or HTTP. You can also configure the settings to control how the data is streamed and how it is processed by the downstream instances.

Overall, centralized streaming in Splunk provides a powerful way to distribute data to multiple downstream instances, allowing for greater flexibility, efficiency, and redundancy in your data analysis processes.

Transforming:

Transforming, in the context of Splunk, refers to modifying the data during the search process to extract and transform specific fields or values, or to create new fields or values. This can be useful for cleaning up and normalizing data, extracting relevant information, and creating more meaningful visualizations and reports.

There are several ways to transform data in Splunk, including using search commands, field extractions, and calculated fields.

  1. Search commands: Splunk provides many built-in search commands that can be used to transform data during the search process. For example, the “rex” command can be used to extract fields using regular expressions, while the “eval” command can be used to create new fields or modify existing ones.
  2. Field extractions: Field extractions allow you to extract fields from your data automatically, using predefined patterns or regular expressions. This can be done using the “Field Extractor” in the Splunk GUI, or by manually configuring field extractions using the “props.conf” and “transforms.conf” configuration files.
  3. Calculated fields: Calculated fields allow you to create new fields based on existing fields or calculations. This can be done using the “eval” command or by defining calculated fields in the “fields.conf” configuration file.

Transforming data in Splunk can help you to make sense of complex data sets, and to generate insights that would be difficult or impossible to obtain otherwise. By extracting relevant information, normalizing data, and creating new fields or values, you can create more accurate and meaningful visualizations and reports that can inform business decisions and drive results.

Generating:

Generating, in the context of Splunk, refers to creating new data or events during the search process. This can be useful for generating synthetic data, filling in gaps in existing data, or creating alerts based on specific conditions.

There are several ways to generate data in Splunk, including using search commands, data models, and scripted inputs.

  1. Search commands: Splunk provides many built-in search commands that can be used to generate data during the search process. For example, the “gentimes” command can be used to generate events at specified time intervals, while the “makeresults” command can be used to generate synthetic data.
  2. Data models: Data models allow you to create relationships between different types of data, and to generate new events based on those relationships. For example, you can create a data model that relates web server logs to user authentication logs, and use that data model to generate events that indicate when a user accessed a specific resource on the web server.
  3. Scripted inputs: Scripted inputs allow you to generate data by executing scripts or programs on the Splunk server. For example, you can use a scripted input to generate events based on data from an external API or database.

Generating data in Splunk can help you to fill in gaps in your data, create synthetic data for testing or simulation purposes, and generate alerts based on specific conditions. By creating new events or data during the search process, you can gain deeper insights into your data and make more informed business decisions.

Orchestrating:

Orchestrating, in the context of Splunk, refers to using Splunk to coordinate and automate workflows across different systems and applications. This can be useful for streamlining business processes, reducing manual effort, and improving overall efficiency.

There are several ways to orchestrate workflows in Splunk, including using workflow actions, alerts, and custom scripts.

  1. Workflow actions: Workflow actions allow you to define actions that can be taken in response to search results or events. For example, you can define a workflow action that triggers a script or program, sends an email, or creates a JIRA ticket. Workflow actions can be triggered manually or automatically, based on specific conditions.
  2. Alerts: Alerts allow you to define conditions that trigger an action when met. For example, you can define an alert that triggers a script or program when a certain event occurs, such as a server going offline or a security breach being detected.
  3. Custom scripts: Splunk provides several ways to execute custom scripts and programs, including using scripted inputs and search commands. These custom scripts can be used to orchestrate workflows across different systems and applications, such as triggering a script to restart a server or running a script to generate a report.

Orchestrating workflows in Splunk can help you to automate repetitive tasks, streamline business processes, and improve overall efficiency. By using workflow actions, alerts, and custom scripts, you can coordinate activities across different systems and applications, reducing manual effort and freeing up time for other important tasks.

Dataset processing:

Dataset processing in the context of Splunk refers to the different techniques and tools that are used to prepare, analyze and manipulate large volumes of data stored in Splunk indexes. The objective of dataset processing is to transform raw data into meaningful insights that can be used to make informed decisions.

There are several techniques and tools available in Splunk for dataset processing, including:

  1. Search commands: Splunk provides a large number of built-in search commands that can be used to process data. These commands can be used to filter, aggregate, and transform data, as well as to create reports, charts, and dashboards.
  2. Field extractions: Splunk allows you to extract fields from raw data automatically or manually. Field extractions can be used to parse out important data fields from log data, transaction data or other types of data. This makes it easier to analyze and report on specific data fields.
  3. Data models: Data models in Splunk allow you to define relationships between different types of data. This makes it easier to analyze and report on complex data sets that may contain data from different sources or applications.
  4. Pivot: Splunk pivot allows you to interactively explore and analyze data. Pivot tables allow you to group and aggregate data based on specific fields or values. This makes it easier to gain insights into data relationships and patterns.
  5. Machine learning: Splunk supports machine learning models for anomaly detection, predictive analytics, and data clustering. This allows you to use advanced algorithms to identify patterns and relationships that may not be obvious with simple statistical analysis.

By utilizing the various techniques and tools available in Splunk, you can transform large volumes of raw data into meaningful insights. Dataset processing in Splunk enables you to filter, aggregate, and transform data to create reports, charts, and dashboards that support informed decisions.