I am working on hadoop hdfs 2.7.1. I have set up a single node cluster having one datanode. But now i need to set up three datanodes on the same machine. I tried using various methods available on the internet but am unable to start the hadoop cluster having three datanodes on the same machine. Please help me.
You can run a multi-node cluster on a single machine using Docker containers. The guys at SequenceIQ, a company that was recently acquired by Hortonworks, even prepared Docker images that you can download. See here:
http://blog.sequenceiq.com/blog/2014/06/19/multinode-hadoop-cluster-on-docker/
Related
I'm new to big data. And I have a question about the installation of hadoop.
Currently I use an image on VirtualBox, but I would like to create a cluster on the openstack. At first I thought I just need to instantiate a hadoop image on the openstack or install several instances and use the hadoop docker image.
But I found several examples of the Sahara openstack. Knowing that I already have an openstack shared with several people, is it possible to create a hadoop cluster without going through openstack Sahara? Or is it not recommended?
Not sure about "Sahara Openstack", but you can surely create Hadoop cluster using VM nodes on openstack.
Single node installation guide
http://tecadmin.net/setup-hadoop-2-4-single-node-cluster-on-linux/#
Yes, its possible to create Hadoop cluster on OpenStack cloud without using OpenStack sahara. You can launch 3 Virtual machines on OpenStack, and assign floating IP to these virtual machines.
One can be used as Master and other 2 as slaves. You can follow the Hadoop multinode installation steps on these virtual machines and connect them using SSH configuration which will be mentioned in Hadoop multinode setup guide.
You can also write automated shell script for launching Hadoop on OpenStack.
I've seen searching for a way to start docker on multiple physical machines and connect them to a hadoop cluster, so far I only found ways to start a cluster locally on 1 machine. Is there a way to do this?
You can very well provision a multinode hadoop cluster with docker.
Please look at some posts below which will give you some insights on doing it:
http://blog.sequenceiq.com/blog/2014/06/19/multinode-hadoop-cluster-on-docker/
Run a hadoop cluster on docker containers
Sorry if my question appears to be naïve. We are planning to use CDH 5.3.0 or 5.4.0. We want to implement a multi-node cluster.
The example multi-node installations that I have seen/read on different blogs/resources have master and slaves on different hosts.
However, we are restrained by the number of hosts. We have only 2 powerful hosts ( 32 cores 400+ GB RAM), so if we decide to have master on one and slave on other, we will end up with only one slave. My questions are :
Is it possible to have master and slave on the same hosts?
Can I have more than one slave node on a single host.
Also does one need to pay to use Cloudera Manager or it is open-source like the rest of the components.
If you can point me in the direction of some resource which would help me understand above scenarios it would be helpful.
Thanks for your help.
Regards,
V
old question but no and wrong answer:
yes, it is possible to install Master & Worker services on a single host.
e.g. HDFS (NameNode and Datanode). You can even install a full cloudera or Hortonworks installation with ALL services on a single host if it is powerfull enough, but i would only recommend it for POC or testcases.
If you use cloudera or hortonworks without virtualization it is not possible to run multiple instances of the SAME worker services e.g. datanode on the same host. 1 Host 1 worker instance. everything else would not make sense.
Cloudera is a package of multiple open source projekt (Hadoop,Spark....) and other closed source parts like cloudera manager and other enterprise closed source features. But everything you need is free even for commercial use with the community licence.
Right now (2017): only cloudera navigator is the big feature which is not part of the community edition
Yes you can configure namenode and datanode both on a single node.
You cannot have more than two datanodes on a single machine.
Cloudera is open-source hadoop distribution.
I like to study about Hadoop multinode setup and installation, by referring the above tutorial I understand that single node cluster environment can be used as node for the multinode cluster
http://bigdatahandler.com/hadoop-hdfs/hadoop-multi-node-cluster-setup/
Currently I am learning Hadoop using Horton sandbox, can we use a sandbox system as a single node environment?
If not what is the difference between sandbox and traditional Hadoop cluster installation
The sandbox images (from Hortonworks and Cloudera) provide the user with a pre-configured development environment with all the usual tools already available and installed (pig, hive etc.). Since the image is a single "system" it is set-up such that the hadoop cluster is single-node: i.e. everything - HDFS, Hadoop map-reduce etc. - is local to that image. That is a massive benefit, as anyone who has set up a hadoop cluster will tell you! It allows you to get up-and-running with very little operational overhead.
What these sandboxes do not provide, however, is realistic cluster behaviour as you have only one node. But there other possibilities - tools such as Vagrant and Docker - that would allow you to do this (I have not tried it myself).
The big data handler link you shared seems to be about combining several of these standalone, inherently single-node "clusters" so that you have something more realistic. But I would guess setting this up so that YARN, Zookeeper and other services are not duplicated comes with a not insignificant challenge.
I am new to cloudera, I installed cloudera in my system successfully I have two doubts,
Consider a machine with some nodes already using hadoop with some data, Can we install Cloudera to use the existing Hadoop without made any changes or modifaction on data stored existing hadooop.
I installed Cloudera in my machine, I have another three machines to add those as clusters, I want to know, Am i want install cloudera in those three machines before add those machines as clusters ?, or Can we add a node as clusters without installing cloudera on that purticular nodes?.
Thanks in advance can anyone, please give some information about the above questions.
Answer to questions -
1. If you want to migrate to CDH from existing Apache Distribution, you can follow this link
Excerpt:
Overview
The migration process does require a moderate understanding of Linux
system administration. You should make a plan before you start. You
will be restarting some critical services such as the name node and
job tracker, so some downtime is necessary. Given the value of the
data on your cluster, you’ll also want to be careful to take recent
back ups of any mission-critical data sets as well as the name node
meta-data.
Backing up your data is most important if you’re upgrading from a
version of Hadoop based on an Apache Software Foundation release
earlier than 0.20.
2.CDH binary needs be installed and configured in all the nodes to have a CDH based cluster up and running.
From the Cloudera Manual
You can migrate the data from a CDH3 (or any Apache Hadoop) cluster to a CDH4 cluster by
using a tool that copies out data in parallel, such as the DistCp tool
offered in CDH4.
Other sources
Regarding your second question,
Again from the manual page
Important:
Before proceeding, you need to decide:
As a general rule:
The NameNode and JobTracker run on the the same "master" host unless
the cluster is large (more than a few tens of nodes), and the master
host (or hosts) should not
run the Secondary NameNode (if used), DataNode or TaskTracker
services. In a large cluster, it is especially important that the
Secondary NameNode (if used) runs on a separate machine from the
NameNode. Each node in the cluster except the master host(s) should
run the DataNode and TaskTracker services.
Additionally, if you use Cloudera Manager it will automatically do all the setup necessary i.e install the necessary selected components on the nodes in the cluster.
Off-topic: I had a bad habit of not referrring the manual properly. Have a clear look at it, it answers all our questions
Answer to your second question,
you can add directly, with installation few pre requisites like openssh-clients and firewalls and java.
these machines( existing node, new three nodes) should accept same username and password (or) you should set passwordless ssh to these hosts..
you should connect to the internet while adding the nodes.
I hope it will help you:)