The Cloudera Certified Associate Administrator (CCA-131) exam is intended to assess candidates’ cluster administration and core system skills. Furthermore, this certification demonstrates a candidate’s skills in a way that organizations and companies deploying Cloudera in the enterprise require. The Cloudera CCA Administrator certification exam is a hands-on, practical exam that is based on Cloudera technologies. Furthermore, it is a remote-proctored exam that can be taken from any location at any time. To help you prepare for the Exam CCA-131: Cloudera Certified Associate Administrator interview we have curated a list of questions and answers:
1. What exactly is Cloudera?
- Firstly, Cloudera is redefining enterprise data management by introducing The Enterprise Data Hub, the first unified Platform for Big Data. Secondly, cloudera provides enterprises with a single location to store, process, and analyze all of their data, allowing them to maximize the value of their existing investments while also enabling fundamental new ways to derive value from their data.
- Cloudera, which was founded in 2008, was the first and continues to be the leading provider and supporter of Apache Hadoop for the enterprise. Cloudera also provides software to address business-critical data challenges such as storage, access, management, analysis, security, and search.
- Cloudera’s top priority is customer success. We’ve enabled long-term, successful deployments for hundreds of customers, managing petabytes of data across multiple industries.
2. What exactly is an enterprise data hub?
An enterprise data hub is a single location where all of your data can be stored in its original fidelity for as long as desired or required; it is integrated with existing infrastructure and tools; and it has the flexibility to run a variety of enterprise workloads, including batch processing, interactive SQL, enterprise search, and advanced analytics, as well as the robust security, governance, data protection, and management that enterprises require. Leading organizations are changing the way they think about data with an enterprise data hub, transforming it from a cost to an asset.
3. What are some examples of common enterprise data hub use cases?
- Firstly, Transformation and enrichment: Transform and process large amounts of data in a more timely, dependable, and cost-effective manner (for loading into the data warehouse, for example).
- Secondly, Active archiving allows you to access data that would otherwise be taken offline (typically to tape) due to the high cost of actively managing it.
- Next, Self-service exploratory BI: Allow users to securely explore data using traditional interactive business intelligence tools such as SQL and keyword search.
- Advanced analytics: Instead of forcing users to examine samples of data or snapshots from short time periods, allow them to combine all historical data in its entirety for comprehensive analyses.
4. Why is open source important to customers?
Customers benefit greatly from open source licensing and development, including freedom from lock-in, free no-obligation evaluation, global rapid innovation, and community-driven development. Customer freedom from lock-in is especially important when components that store and process data are involved.
5. How do I set up TLS encryption in Cloudera manager?
- Firstly, when you configure authentication and authorization on a cluster, Cloudera Manager Server sends sensitive information, such as Kerberos keytabs and configuration files containing passwords, over the network to cluster hosts. You must configure TLS encryption between Cloudera Manager Server and all cluster hosts to secure this transfer.
- Next, TLS encryption is also used to secure HTTPS-based client connections to the Cloudera Manager Admin Interface.
- Further, TLS authentication is also supported by Cloudera Manager. A malicious user can add a host to Cloudera Manager without using certificate authentication by installing the Cloudera Manager Agent software and configuring it to communicate with Cloudera Manager Server. To avoid this, you must install certificates on each agent host and configure Cloudera Manager Server to accept certificates.
6. What exactly is cloudera search in Exam CCA-131: Cloudera Certified Associate Administrator?
Cloudera Search: Provides near-real-time access to Hadoop and HBase data that has been store or ingested. Search offers near-real-time indexing, batch indexing, full-text exploration, and navigated drill-down, as well as a simple full-text interface that requires no SQL or programming knowledge. Search, which is fully integrated into the data-processing platform, makes use of the CDH storage system, which is flexible, scalable, and robust. This eliminates the need for large data sets to be moved across infrastructures in order to perform business tasks.
7. What is data encryption all about?
Data Encryption and Key Management – Data encryption and key management provide an important layer of protection against potential threats from malicious actors on the network or in the data center. Encryption and key management are also necessary for meeting key compliance initiatives and maintaining the integrity of your enterprise data.
8. What exactly is impala security?
Impala includes a fine-grained Hadoop authorization framework based on the open-source Sentry project. Impala 1.1.0 introduced Sentry authorization. Sentry, in conjunction with the Kerberos authentication framework, raises Hadoop security to a new level required for highly regulated industries such as healthcare, financial services, and government. Impala also has auditing capabilities.
9. How to execute file system commands via HTTPFS?
Cloudera provides the HttpFS role as part of the HDFS service, which you can assign to hosts during initial setup or at any time. Finish by selecting the host to which you want to assign HttpFS (Client Deploy). Log in to any node in the cluster now to execute filesystem commands.
10. What is the way to restore a snapshot of an HDFS directory?
Go to Cloudera Manager > HDFS > File Browser to restore the snapshot. In the File Browser, navigate to “/user/test” and select “Restore Directory from Snapshot” from the dropdown menu.
11. How to efficiently copy data within a cluster/between clusters?
DistCp (distributed copy) is a tool for large inter/intra-cluster HDFS data copying. It makes use of MapReduce for distribution, error handling and recovery, and reporting. It converts a list of files and directories into input to map tasks, each of which copies a partition of the files in the source list. Next, it is much faster and more effective than the standard “cp” command.
To copy data between HDFS directories in the same cluster:
hadoop distcp /source_path /user/destination_path
12. What is the way to benchmark the cluster (I/O, CPU, network)?
Benchmarking is the process of stress testing the cluster’s resources. It’s very useful for understanding your cluster’s performance and ensuring that it’s performing as expected before going live. We will test the speed with which files are read/written in HDFS, the time required for mappers/reducers to process a given size of data, the performance, and so on. By running the test jars included with the Cloudera distribution, we can easily benchmark the cluster.
13. What are some of the benefits of Cloudera?
The following are some of Cloudera’s benefits:
- Firstly, There are no silos.
- Secondly, A cloud experience that is adaptable.
- Next, Data analytics with multiple functions
- Further, Enterprise-level security and governance
- Increases the value of data to the business.
14. What exactly is Cloudera Impala?
Cloudera Impala is a Cloudera Enterprise-supported Apache Impala that provides access to the data store in CDH without requiring the Java skills require for MapReduce jobs. It is an open-source massively parallel processing (MPP) SQL query engine that is commonly use for processing massive amounts of data stored in the Hadoop cluster.
15. Explain Kerberos in Exam CCA-131: Cloudera Certified Associate Administrator.
Kerberos is a computer network security protocol that authenticates client-server applications and verifies user identities by utilizing secret-key cryptography and a trusted third party. It authenticates service requests sent between two or more trusted hosts over an untrusted network like the internet.
16. What is Apache Tika?
Apache Tika(TM) is a Java-based content detection and analysis framework. The Apache Software Foundation is in charge of it. It is also a toolkit for detecting and extracting metadata and structured text content from a variety of documents using pre-existing parser libraries.
17. How to configure HDFS ACLs?
Go to HDFS > Configuration, search for ACL, and check the box next to “Enable Access Control Lists.” Save your changes and re-deploy the old configuration. Cloudera Manager would display the changes to the deployment configuration. Continue by clicking “Restart Stale Services.”
18. How to set up a local CDH repository?
- Firstly, Download the repo to your machine
- Secondly, Install webserver
- Next, Install yum-utils and createrepo
- Fetch the rpms of CDH5 repo to your server
- Also, Create a repo file
- Local CDH repository created
19. What is the way to insert CDH using Cloudera Manager?
- Firstly, Create a Repository.
- Next, Set up the JDK.
- Step 3: Set up the Cloudera Manager Server.
- Step 4: Setup Databases. Install and set up MariaDB. MySQL should be installed and configure. Install and set up PostgreSQL.
- Further, Set up the Cloudera Manager Database in
- Step 6: Install CDH and Other Software in
- Step 7: Create a Cluster
20. What do you understand by cluster rebalancing?
Cluster rebalancing ensures that every non-virtual node in a DataStax Enterprise cluster manages the same amount of data. A cluster is rebalancing. To ensure that each node in a DataStax Enterprise cluster manages an equal amount of data, rebalance a non-node cluster.
21. Define rack topology script.
HDFS uses topology scripts to determine node rack location and then replicates block data to redundant racks.
22. How to resolve errors/warnings in Cloudera Manager?
This is a typical scenario-based question, and the answer is solely dependent on the errors/warnings that appear in the cluster. Here are some examples:
Warnings could include a lack of space, a poor state of service, insufficient resource allocation, and so on. The errors could be due to log directories being full, services being unavailable, or other critical events. In these cases, clicking on the error message will take you to the service/instance status page. If the problem is a lack of space, log in to the server and navigate to the appropriate log directory, where you can free up some space by zipping, moving, or deleting files. Calculate the total memory available in the node, the memory allocated to the services, and try to balance the allocation without affecting the service/server.
23. Explain Avro.
Avro is an open-source project that provides data serialization and data exchange services to facilitate the exchange of big data between programs written in any language. If the problem is a lack of space, log in to the server and navigate to the appropriate log directory, where you can free up some space by zipping, moving, or deleting files.
24. What do you understand by cluster template?
A cluster template is a reusable template. The cluster template’s purpose is to create multiple Data Hub clusters with Cloudera Runtime settings. A Kubernetes cluster template is a blueprint of a Kubernetes cluster that contains the necessary configuration.
25. Where can I find CDH libraries?
CDH libraries can be found in the directories listed below:
- + 3rd party libraries are located in lib subdirectories
26. How to perform OS-level configuration for Hadoop installation?
The following items are included in the OS configuration:
- Enabling NTP
- Configuring Network Names (hostnames/FQDNs)
- Disabling SELinux
- Disabling the Firewall
27. How do you get the hdfs file system report? What about disc availability and the number of active nodes?
- Firstly, Run the fsck command on namenode as $HDFS_USER: su – hdfs -c “hdfs fsck / -files -blocks -locations > dfs-new-fsck-1.log” .
- Secondly, , Run hdfs namespace and report the results.
- Next, Examine the namespace report before and after the upgrade.
- Last but not the least, Check that the read and write to hdfs functions properly.
28. What is the most important hdfs command list?
The following are the most important hdfs commands:
- ls: This command is use to list all the files.
- mkdir: To create a directory.
- touchz: It creates an empty file.
- copyFromLocal (or) put: To copy files/folders from local file system to hdfs store.
- cat: To print file contents.
- copyToLocal (or) get: To copy files/folders from hdfs store to local file system.
29. What are the two types of metadata stored on a NameNode server?
A NameNode server can store two types of metadata:
- Disk Metadata – This includes the edit log and the FSImage.
- Metadata in RAM – This is where you’ll find information about DataNodes.
30. What happens if a ResourceManager fails while an application is running in a high availability cluster?
There are two ResourceManagers in a high availability cluster: one active and one standby. In the event that a ResourceManager fails in a high availability cluster, the standby is elected as active and instructs the ApplicationMaster to abort. The ResourceManager regains its running state by utilizing the container statuses sent by all node managers.