Splunk Interview Questions And Answers – Introduction
Below are the topmost useful Splunk Interview Questions and Answers. These Top Questions are divided into two parts are as follows:
Part 1 – Splunk Interview Questions (Basic)
This first part covers basic Interview Questions and Answers.
1. What is Splunk? Why is Splunk used for analyzing machine data?
One of the most used analytics tools out there is Microsoft Excel and the drawback with it is that Excel can load only up to 1048576 rows and the machine data are generally huge. Splunk comes in handy in dealing with machine-generated data (big data), the data from servers, devices, or networks can be easily loaded into Splunk and can be analyzed to check for any threat visibility, compliance, security, etc. it can also be used for application monitoring.
2. Explain how Splunk works?
This is the common Splunk Interview Questions asked in an interview. Data is loaded into Splunk using the forwarder which acts as an interface between the Splunk environment and the outside world, then this data is forwarded to an indexer where the data is either stored locally or on a cloud. The indexer indexes the machine data and stores it in the server. Search Head is the GUI that is provided by Splunk for searching and analyzing (searches, visualizes, analyzes, and performs various other functions) the data.
The deployment server manages all the components of Splunk like indexer, forwarder, and search head in Splunk environment.
3. What are the common port numbers used by Splunk?
Common ports numbers on which services are run (by default) are:
|Management / REST API||8089|
|Search head / Indexer||8000|
|Search head||8065, 8191|
|Indexer cluster peer node / Search head cluster member||9887|
Let us move to the next Splunk interview questions.
4. Why use only Splunk?
There are many alternatives for Splunk which give a lot of competition to it some of them are as below:
• ELK/Logstash (open source)
Elasticsearch is used for searching it’s like the search head in Splunk, Log stash is for data collection which is similar to the forwarder used in Splunk, and Kibana is used for data visualization(search head does the same in Splunk)
• Graylog (open source with commercial version)
Graylog is yet another tool that was named last year with its release 1.0. Similar to the ELK stack Graylog also has different components it uses Elasticsearch as its core component but the data is stored in Mongo DB and uses Apache Kafka. It has two versions one core version which is available for free and the enterprise version which comes with functions like archiving.
• Sumo Logic (cloud service)
So what makes Splunk best among all is that Splunk comes as a single package of the data collector, storage as well as analytics tool inbuilt. Splunk is also scalable and provides support/professional help for its enterprise edition.
5. Briefly, explain the Splunk Architecture?
The below picture gives a brief overview of the Splunk architecture and its components.
Part 2 – Splunk interview questions (Advanced)
Let us now have a look at the advanced interview questions.
6. What are the components of Splunk architecture?
There are four components in the Splunk architecture. They are:
- Indexer: Indexes machine data
- Forwarder: Forwards logs to index
- Search head: Provides GUI for searching
- Deployment server: Manages the Splunk components(indexer, forwarder and search head) in a distributed environment
7. Give a few use cases of Knowledge Objects?
This is the frequently asked Splunk interview questions in an interview. Knowledge objects can be used in many domains. Few examples are:
- Application Monitoring: This can be used to monitor applications in real-time with configured alerts which will notify the admins/users when an application crashes.
- Physical Security: In the event of a flood /volcanic etc the data can be used to draw insights if your organization is dealing with any such data.
- Network Security: You can create a secure environment by blacklisting the IP of unknown devices thereby reducing data leaks in any organization.
- Employee Management: Employee attrition is one of the challenges that is faced by any organization and during notice period the employee’s activity can be tracked in order to protect the organization’s data thereby monitoring their activity and restricting any other employee in notice period not to do the same.
8. Explain Search Factor (SF) & Replication Factor (RF)?
These are the terminologies that are used in Splunk clustering techniques. Indexer cluster is a specially configured group of Splunk Enterprise indexers that replicates external data and is used for disaster recovery.
In terms of the Splunk documentation search, the factor can be described as “The number of searchable copies of data that an indexer cluster maintains. The default value of the search factor is 2” whereas the replication factor is defined as the number of copies of data that the cluster maintains.
Indexer cluster has both a Search Factor and a Replication Factor whereas Search head cluster has only a Search Factor
9. What are Splunk buckets? Explain the bucket lifecycle?
The directories in which the indexed data is stored is known as Splunk buckets and these have events of a certain period. The lifecycle of Splunk bucket includes four stages hot, warm, cold, frozen and thawed.
- Hot: This bucket contains the recently indexed data and is open for writing.
- Warm: After the data falls in hot bucket depending on your data policies it moves to warm buckets
- Cold” The next stage after warm is the cold stage wherein the data can’t be edited.
- Frozen: By default the indexer deletes the data from frozen buckets but these can also be archived.
- Thawed: The retrieval of information from archived files (frozen buckets) is known as thawing.
10. Why should we use Splunk Alert? What are the different options while setting up Alerts?
The state of being watchful for any possible error is known as alert and in Splunk, environment alerts can arise due to any connection failures or security violations or breaking of any user-created rules.
For example, sending notifications or a report of the users who have failed to login after utilizing their three attempts in a portal to the application administrator.
Different options that are available while setting up alerts are:
- A webhook can be created to write the alerts to hipchat or GitHub.
- Add results, .csv or pdf or in line with the body of the message so that the root cause of the alert can be identified.
- Tickets can be created and alerts can be throttled from a machine or an IP.
This has been a guide to List Of Splunk Interview Questions And Answers so that the candidate can crackdown these Interview Questions And Answers easily. You may also look at the following articles to learn more –