Author Archives: Justin Kestelyn

How-to: Use the New Apache Oozie Database Migration Tool

Categories: How-to Oozie

Updated 11/22/16 – Important: All features below are working on CDH 5.9.0 and CM 5.9.0 and above. 

This tool makes Oozie migrations off Apache Derby (or any other supported database) easy, in addition to streamlining upgrades.

The Apache Oozie server is a stateless web application by design, with all information about running and completed workflows, coordinator jobs, and bundle jobs stored in a relational database.

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Inside the Apache Solr JSON Facet API

Categories: CDH Search

Solr 5 includes a completely re-written faceted search and analytics module with a structured JSON API to control the faceting and analytics commands. Here’s how it works.

Since I joined Cloudera a few years ago to help bring search-powered analytics to Cloudera’s platform, I’ve been working actively upstream alongside the rest of the Solr community to develop new functionality that will drive more interesting applications on Cloudera Search (which is based on an integration of Solr with the Apache Hadoop ecosystem).

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How-to: Use the New HDFS Intra-DataNode Disk Balancer in Apache Hadoop

Categories: CDH Hadoop HDFS

HDFS now includes (shipping in CDH 5.8.2 and later) a comprehensive storage capacity-management approach for moving data across nodes.

In HDFS, the DataNode spreads the data blocks into local filesystem directories, which can be specified using dfs.datanode.data.dir in hdfs-site.xml. In a typical installation, each directory, called a volume in HDFS terminology, is on a different device (for example, on separate HDD and SSD).

When writing new blocks to HDFS,

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How-to: Secure Apache Solr Collections and Access Them Programmatically

Categories: Platform Security & Cybersecurity Search Sentry

Learn how to secure your Solr data in a policy-based, fine-grained way.

Data security is more important than ever before. At the same time, risk is increasing due to the relentlessly growing number of device endpoints, the continual emergence of new types of threats, and the commercialization of cybercrime. And with Apache Hadoop already instrumental for supporting the growth of data volumes that fuel mission-critical enterprise workloads, the necessity to master available security mechanisms is of vital importance to organizations participating in that paradigm shift.

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How-to: Do Scalable Graph Analytics with Apache Spark

Categories: Data Science Graph Processing How-to Spark

Get started with scalable graph analysis via simple examples that utilize GraphFrames and Spark SQL on HDFS.

Graphs—also known as “networks”—are ubiquitous across web applications. As a refresher, a graph consists of nodes and edges. A node can be any object, such as a person or an airport, and an edge is a relation between two nodes, such as a friendship or an airline connection between two cities.

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