Remote-access Guide

hbase standalone remote access

by Coleman Dicki Published 2 years ago Updated 2 years ago
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What is a standalone instance of HBase?

A standalone instance has all HBase daemons — the Master, RegionServers, and ZooKeeper — running in a single JVM persisting to the local filesystem. It is our most basic deploy profile.

How do I start HBase on an existing HDFS instance?

To home HBase on an existing instance of HDFS, set the hbase.rootdir to point at a directory up on your instance: e.g. hdfs://namenode.example.org:8020/hbase. For more on this variant, see the section below on Standalone HBase over HDFS. The bin/start-hbase.sh script is provided as a convenient way to start HBase.

How do I set the Java_home variable in HBase?

You must set the JAVA_HOME environment variable before starting HBase. To make this easier, HBase lets you set it within the conf/hbase-env.sh file. You must locate where Java is installed on your machine, and one way to find this is by using the whereis java command.

How to use htable in HBase?

You have a class called HTable, an implementation of Table in HBase. This class is used to communicate with a single HBase table. While instantiating this class, it accepts the configuration object and the table name as parameters. You can instantiate the HTable class as shown below.

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How do I connect to HBase server?

ProcedureProvide Hadoop Identity. ... Provide HBase Identity. ... The path to the core-site. ... Select Authentication method. ... In the HBase Namespace and Target table, specify the table name to which you want to connect and namespace in which it is created (if different than the default namespace).

Can HBase run without Hadoop?

HBase can be used without Hadoop. Running HBase in standalone mode will use the local file system. Hadoop is just a distributed file system with redundancy and the ability to scale to very large sizes.

How do I start HBase master service?

Start the cluster by running the start-hbase.sh command on node-1. ZooKeeper starts first, followed by the Master, then the RegionServers, and finally the backup Masters. Run the jps command on each node to verify that the correct processes are running on each server.

How do I access HBase table?

To access the HBase shell, you have to navigate to the HBase home folder. You can start the HBase interactive shell using “hbase shell” command as shown below. If you have successfully installed HBase in your system, then it gives you the HBase shell prompt as shown below.

What is HBase standalone mode?

Standalone mode is what is described in the Section 1.2, “Quick Start” section. In standalone mode, HBase does not use HDFS -- it uses the local filesystem instead -- and it runs all HBase daemons and a local ZooKeeper all up in the same JVM. Zookeeper binds to a well known port so clients may talk to HBase.

How do I install HBase in standalone mode?

Installing HBase in Standalone Mode Download the latest stable version of HBase form http://www.interior-dsgn.com/apache/hbase/stable/ using “wget” command, and extract it using the tar “zxvf” command. See the following command. Shift to super user mode and move the HBase folder to /usr/local as shown below.

What is HBase master?

The HBase Master coordinates the HBase Cluster and is responsible for administrative operations. A Region Server can serve one or more Regions. Each Region is assigned to a Region Server on startup and the master can decide to move a Region from one Region Server to another as the result of a load balance operation.

How do I start-HBase in Windows?

Run start-hbase.cmdOpen command prompt and cd to HBase' bin directory.Run hbase shell [should connect to the HBase server]Try creating a table.create 'emp','p'list [Table name should get printed]put 'emp','emp01','p:fn','First Name'scan 'emp' [The row content should get printed]

How do I join two tables in HBase?

Using Hive or Impala is costly when data is to large and we face issue like Hbase kill(region server Down) . so it is convenient when data is small but not for large Data. In mapreduce take Hbase table object to take one table and by extending tablemapper use 2nd table. By this way you can join 2 tables.

What is the difference between hive and HBase?

HBase is an open-source NoSQL database that runs on Apache Hadoop and HDFS. This expandable storage can hold unlimited data. Hive is a Map Reducebased SQL engine built on HDFS.

Is HBase horizontally scalable?

HBase is a distributed column-oriented database built on top of the Hadoop file system. It is an open-source project and is horizontally scalable.

Can HBase access Hive table?

HBase and Apache Hive are tightly integrated, allowing you run massively parallel processing workloads directly on data stored in HBase. To use Hive with HBase, you can usually launch them on the same cluster. You can, however, launch Hive and HBase on separate clusters.

Is HBase based on Hadoop?

What is HBase? HBase is a column-oriented non-relational database management system that runs on top of Hadoop Distributed File System (HDFS).

What is the difference between HBase and Hadoop?

Hadoop and HBase are both used to store a massive amount of data. But the difference is that in Hadoop Distributed File System (HDFS) data is stored is a distributed manner across different nodes on that network. Whereas, HBase is a database that stores data in the form of columns and rows in a Table.

Can hive run without Hadoop?

Hive needs hadoop libraries, and using hive to execute queries requires hadoop and map reduce.

Can we run Apache spark without Hadoop?

You can Run Spark without Hadoop in Standalone Mode Spark and Hadoop are better together Hadoop is not essential to run Spark. If you go by Spark documentation, it is mentioned that there is no need for Hadoop if you run Spark in a standalone mode. In this case, you need resource managers like CanN or Mesos only.

kirillsavine commented on Jun 6, 2017

I have been trying to setup HBase for the first time. I am able to successfully run the native Hbase shell on the server. But I am not able to connect remotely via a client.

Here are last 3 lines from Hbase log

It says that connection from 192.168.0.11 (client IP) is accepted, but immediately after that it throws an Exception causing close of session:

wbolster commented on Jun 6, 2017

seems like you are not connecting to the thrift server, which generally listens on another port.

kirillsavine commented on Jun 6, 2017

Thank you so much for your answer! I just figured I need to use port 9090

How to get stable version of hbase?

Download the latest stable version of HBase form http://www.interior-dsgn.com/apache/hbase/stable/ using “wget” command, and extract it using the tar “zxvf” command. See the following command.

How many servers can you start with HBase?

Using the “local-master-backup.sh” you can start up to 10 servers. Open the home folder of HBase, master and execute the following command to start it.

What is a Hadoop site.xml file?

The hdfs-site.xml file contains information such as the value of replication data, namenode path, and datanode path of your local file systems, where you want to store the Hadoop infrastructure.

What is core site xml?

The core-site.xml file contains information such as the port number used for Hadoop instance, memory allocated for file system, memory limit for storing data, and the size of Read/Write buffers.

Why is SSH required in Hadoop?

SSH setup is required to perform different operations on the cluster such as start, stop, and distributed daemon shell operations. To authenticate different users of Hadoop, it is required to provide public/private key pair for a Hadoop user and share it with different users.

What is the default port number for Hadoop?

The default port number to access Hadoop is 50070. Use the following url to get Hadoop services on your browser.

Where are the configuration files in Hadoop?

You can find all the Hadoop configuration files in the location “$HADOOP_HOME/etc/hadoop”. You need to make changes in those configuration files according to your Hadoop infrastructure.

What is an HBase database?

HBase is a column-oriented database and the tables in it are sorted by row. The table schema defines only column families, which are the key value pairs. A table have multiple column families and each column family can have any number of columns. Subsequent column values are stored contiguously on the disk. Each cell value of the table has a timestamp. In short, in an HBase:

What is Apache HBase?

Apache HBase is used to have random, real-time read/write access to Big Data. It hosts very large tables on top of clusters of commodity hardware. Apache HBase is a non-relational database modeled after Google's Bigtable. Bigtable acts up on Google File System, likewise Apache HBase works on top of Hadoop and HDFS.

Why is SSH required in Hadoop?

SSH setup is required to perform different operations on the cluster such as start, stop, and distributed daemon shell operations. To authenticate different users of Hadoop, it is required to provide public/private key pair for a Hadoop user and share it with different users.

What is column oriented database?

Column-oriented databases are those that store data tables as sections of columns of data, rather than as rows of data. Shortly, they will have column families.

What is RDBMS in IT?

Since 1970, RDBMS is the solution for data storage and maintenance related problems. After the advent of big data, companies realized the benefit of processing big data and started opting for solutions like Hadoop.

Can Hadoop process data?

Hadoop can perform only batch processing, and data will be accessed only in a sequential manner. That means one has to search the entire dataset even for the simplest of jobs.

Which database stores large amounts of data?

Applications such as HBase, Cassandra, couchDB, Dynamo, and MongoDB are some of the databases that store huge amounts of data and access the data in a random manner.

How to pass VM options to HBase?

You can pass VM options to the HBase Shell using the HBASE_SHELL_OPTS environment variable . You can set this in your environment, for instance by editing ~/.bashrc, or set it as part of the command to launch HBase Shell. The following example sets several garbage-collection-related variables, just for the lifetime of the VM running the HBase Shell. The command should be run all on a single line, but is broken by the character, for readability.

What is hbase 0.95?

HBase 0.95 introduces the ability to assign a table to a jruby variable. The table reference can be used to perform data read write operations such as puts, scans, and gets well as admin functionality such as disabling, dropping, describing tables.

How many commands can you enter into a HBase shell?

You can enter HBase Shell commands into a text file, one command per line, and pass that file to the HBase Shell.

What is Apache HBase Shell?

The Apache HBase Shell is (J)Ruby 's IRB with some HBase particular commands added. Anything you can do in IRB, you should be able to do in the HBase Shell.

How to run RPC with strong authentication?

To run HBase RPC with strong authentication, you must set hbase.security.authentication to kerberos . In this case, you must also set hadoop.security.authentication to kerberos in core-site.xml. Otherwise, you would be using strong authentication for HBase but not for the underlying HDFS, which would cancel out any benefit.

How are rows sorted in HBase?

Rows in HBase are sorted lexicographically by row key. This design optimizes for scans, allowing you to store related rows, or rows that will be read together, near each other. However, poorly designed row keys are a common source of hotspotting . Hotspotting occurs when a large amount of client traffic is directed at one node, or only a few nodes, of a cluster. This traffic may represent reads, writes, or other operations. The traffic overwhelms the single machine responsible for hosting that region, causing performance degradation and potentially leading to region unavailability. This can also have adverse effects on other regions hosted by the same region server as that host is unable to service the requested load. It is important to design data access patterns such that the cluster is fully and evenly utilized.

What datatypes are supported by the atomic increment?

One supported datatype that deserves special mention are "counters" (i.e., the ability to do atomic increments of numbers). See Increment in Table.

How to install Apache HBase?

As the Apache HBase distributable is just a zipped archive, installation is as simple as unpacking the archive so it ends up in its final installationdirectory. Notice that HBase has to be installed in Cygwin and a good directory suggestion is to use /usr/local/(or [Rootdirectory]usrlocalin Windows slang). You should end up with a /usr/local/hbase-<version>installation in Cygwin.

What is Apache HBase?

Apache HBase (TM)is a distributed, column-oriented store, modeled after Google's BigTable. Apache HBase is built on top of Hadoopfor its MapReduce and distributed file systemimplementation. All these projects are open-source and part of the Apache Software Foundation. As being distributed, large scale platforms, ...

What technologies are required for Apache HBase?

For running Apache HBase on Windows, 3 technologies are required: Java, Cygwin and SSH. The following paragraphs detail the installation of each of the aforementioned technologies. Java. HBase depends on the Java Platform, Standard Edition, 6 Release.

What is setup.exeutility?

For installation, Cygwin provides the setup.exeutilitythat tracks the versions of all installed components on the target system and provides the mechanism for installingor updating everything from the mirror sites of Cygwin.

Is Apache HBase a single node?

This document explains the intricacies of running Apache HBase on Windows using Cygwinas an all-in-one single-node installation for testing and development. The HBase Overviewand QuickStartguides on the other hand go a long way in explaning how to setup HBasein more complex deployment scenario's.

Is Hadoop a Java project?

As being distributed, large scale platforms, the Hadoop and HBase projects mainly focus on *nixenvironmentsfor production installations. However, being developed in Java, both projects are fully portableacross platforms and, hence, also to the Windows operating system. For ease of development the projects rely on Cygwinto have a *nix-like environment on Windows to run the shell scripts.

Does HBase use SSH?

HBase (and Hadoop) rely on SSHfor interprocess/-node communicationand launchingremote commands. SSH will be provisioned on the target system via Cygwin, which supports running Cygwin programs as Windows services!

Starting the HBase Master

On Ubuntu systems (using Debian packages) the HBase Master starts when the HBase package is installed.

Installing and Configuring HBase REST

The script starts the server by default on port 8080. This is a commonly used port and so may conflict with other applications running on the same host.

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