Category Archives: YARN

Untangling Apache Hadoop YARN, Part 1: Cluster and YARN Basics

Categories: Hadoop MapReduce YARN

In this multipart series, fully explore the tangled ball of thread that is YARN.

YARN (Yet Another Resource Negotiator) is the resource management layer for the Apache Hadoop ecosystem. YARN has been available for several releases, but many users still have fundamental questions about what YARN is, what it’s for, and how it works. This new series of blog posts is designed with the following goals in mind:

  • Provide a basic understanding of the components that make up YARN
  • Illustrate how a MapReduce job fits into the YARN model of computation.

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How-to: Secure YARN Containers with Cloudera Navigator Encrypt

Categories: Cloudera Navigator Platform Security & Cybersecurity YARN

Learn how Cloudera Navigator Encrypt bring data security to YARN containers.

With the introduction of transparent data encryption in HDFS, we are now a big step closer toward a secure platform in the Apache Hadoop world. However, there are still gaps in the platform, including how YARN and its applications manage their cache. In this post, I’ll explain how Cloudera Navigator Encrypt fills that particular gap.

Use Case

When a YARN application runs in a cluster it can sometimes spill data to the hard disk,

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Apache Spark Resource Management and YARN App Models

Categories: Spark YARN

A concise look at the differences between how Spark and MapReduce manage cluster resources under YARN

The most popular Apache YARN application after MapReduce itself is Apache Spark. At Cloudera, we have worked hard to stabilize Spark-on-YARN (SPARK-1101), and CDH 5.0.0 added support for Spark on YARN clusters.

In this post, you’ll learn about the differences between the Spark and MapReduce architectures, why you should care,

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How Apache Hadoop YARN HA Works

Categories: Hadoop YARN

Thanks to recent work upstream, YARN is now a highly available service. This post explains its architecture and configuration details.

YARN, the next-generation compute and resource management framework in Apache Hadoop, until recently had a single point of failure: the ResourceManager, which coordinates work in a YARN cluster. With planned (upgrades) or unplanned (node crashes) events, this central service, and YARN itself, could become unavailable.

This post details Cloudera’s recent work in the Hadoop community (YARN-149) to make the ResourceManager (and thus YARN) highly available.

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Apache Hadoop YARN: Avoiding 6 Time-Consuming "Gotchas"

Categories: Hadoop YARN

Understanding some key differences between MR1 and MR2/YARN will make your migration much easier.

Here at Cloudera, we recently finished a push to get Cloudera Enterprise 5 (containing CDH 5.0.0 + Cloudera Manager 5.0.0) out the door along with more than 100 partner certifications.

CDH 5.0.0 is the first release of our software distribution where YARN and MapReduce 2 (MR2) is the default MapReduce execution framework,

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