Community Articles

Find and share helpful community-sourced technical articles.
Announcements
Celebrating as our community reaches 100,000 members! Thank you!
Labels (1)
avatar

Lab Overview

In this lab, we will learn to:

  • Configure Solr to store indexes in HDFS
  • Create a solr cluster of 2 solr instances running on port 8983 and 8984
  • Index documents in HDFS using the Hadoop connectors
  • Use Solr to search documents

Pre-Requisite

  • The lab is designed for the HDP Sandbox. Download the HDP Sandbox here, import into VMWare Fusion and start the VM

LAB

Step 1 - Log into Sandbox

  • After it boots up, find the IP address of the VM and add an entry into your machines hosts file e.g.
192.168.191.241 sandbox.hortonworks.com sandbox    
  • Connect to the VM via SSH (root/hadoop), correct the /etc/hosts entry
ssh root@sandbox.hortonworks.com
  • If running on an Ambari installed HDP 2.3 cluster (instead of sandbox), run the below to install HDPsearch
yum install -y lucidworks-hdpsearch
sudo -u hdfs hadoop fs -mkdir /user/solr
sudo -u hdfs hadoop fs -chown solr /user/solr
  • If running on HDP 2.3 sandbox, run below
chown -R solr:solr /opt/lucidworks-hdpsearch
  • Run remaining steps as solr
su solr

Step 2 - Configure Solr to store index files in HDFS

  • For the lab, we will use schemaless configuration that ships with Solr
    • Schemaless configuration is a set of SOLR features that allow one to index documents without pre-specifying the schema of indexed documents
    • Sample schemaless configruation can be found in the directory /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs
  • Let's create a copy of the sample schemaless configuration and modify it to store indexes in HDFS
    cp -R /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs  /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs_hdfs 
    
  • Open /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs_hdfs/conf/solrconfig.xml in your favorite editor and make the following changes:

1- Replace the section:

                <directoryFactory name="DirectoryFactory"
               >
                </directoryFactory>

with

            <directoryFactory name="DirectoryFactory" class="solr.HdfsDirectoryFactory">
                <str name="solr.hdfs.home">hdfs://sandbox.hortonworks.com/user/solr</str>
                <bool name="solr.hdfs.blockcache.enabled">true</bool>
                <int name="solr.hdfs.blockcache.slab.count">1</int>
                <bool name="solr.hdfs.blockcache.direct.memory.allocation">false</bool>
                <int name="solr.hdfs.blockcache.blocksperbank">16384</int>
                <bool name="solr.hdfs.blockcache.read.enabled">true</bool>
                <bool name="solr.hdfs.blockcache.write.enabled">false</bool>
                <bool name="solr.hdfs.nrtcachingdirectory.enable">true</bool>
                <int name="solr.hdfs.nrtcachingdirectory.maxmergesizemb">16</int>
                <int name="solr.hdfs.nrtcachingdirectory.maxcachedmb">192</int>
            </directoryFactory>

2- set locktype to

<lockType>hdfs</lockType>

3- Save and exit the file

Step 3 - Start 2 Solr instances in solrcloud mode

mkdir -p ~/solr-cores/core1
mkdir -p ~/solr-cores/core2
cp /opt/lucidworks-hdpsearch/solr/server/solr/solr.xml ~/solr-cores/core1
cp /opt/lucidworks-hdpsearch/solr/server/solr/solr.xml ~/solr-cores/core2
#you may need to set JAVA_HOME
#export JAVA_HOME=/usr/lib/jvm/java-1.7.0-openjdk.x86_64
/opt/lucidworks-hdpsearch/solr/bin/solr  start -cloud -p 8983 -z sandbox.hortonworks.com:2181 -s ~/solr-cores/core1
/opt/lucidworks-hdpsearch/solr/bin/solr  restart -cloud -p 8984 -z sandbox.hortonworks.com:2181 -s ~/solr-cores/core2

Step 4 - Create a Solr Collection named "labs" with 2 shards and a replication factor of 2

/opt/lucidworks-hdpsearch/solr/bin/solr create -c labs -d /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs_hdfs/conf -n labs -s 2 -rf 2

Step 5 - Validate that the labs collection got created

224-solrui.png

Step 6 - Load documents to HDFS

  • Upload sample csv file to hdfs. We will index the file with Solr using the Solr Hadoop connectors
hadoop fs -mkdir -p csv
hadoop fs -put /opt/lucidworks-hdpsearch/solr/example/exampledocs/books.csv csv/

Step 7 - Index documents with Solr using Solr Hadoop Connector

hadoop jar /opt/lucidworks-hdpsearch/job/lucidworks-hadoop-job-2.0.3.jar com.lucidworks.hadoop.ingest.IngestJob -DcsvFieldMapping=0=id,1=cat,2=name,3=price,4=instock,5=author -DcsvFirstLineComment -DidField=id -DcsvDelimiter="," -Dlww.commit.on.close=true -cls com.lucidworks.hadoop.ingest.CSVIngestMapper -c labs -i csv/* -of com.lucidworks.hadoop.io.LWMapRedOutputFormat -zk localhost:2181

Step 8 - Search indexed documents

Step 9 - Lab Complete

  • You have sucessfully completed the lab and learnt how to:
    • Store Solr indexes in HDFS
    • Create a Solr Cluster
    • Index documents in HDFS using Solr Hadoop connectors
7,312 Views
Comments
avatar

I would highly recommend chroot'ing the SolrCloud config, otherwise it dumps all entries at the root of a ZooKeeper tree. See https://community.hortonworks.com/content/kbentry/7081/best-practice-chroot-your-solr-cloud-in-zooke... for details.

avatar

@Ali Bajwa getting the following error when running step4, @Artem Ervits got the same error following these steps.

solr@sandbox root]$ /opt/lucidworks-hdpsearch/solr/bin/solr create -c labs -d /opt/lucidworks-hdpsearch/solr/server/solr/configsets/data_driven_schema_configs_hdfs/conf -n labs -s 2 -rf 2
Connecting to ZooKeeper at sandbox.hortonworks.com:2181
Re-using existing configuration directory labs

avatar

Creating new collection 'labs' using command:

http://192.168.197.146:8983/solr/admin/collections?action=CREATE&name=labs&numShards=2&replicationFa...

{

"responseHeader":{

"status":0,

"QTime":1508},

"failure":{"":"org.apache.solr.client.solrj.impl.HttpSolrClient$RemoteSolrException:Error from server at http://192.168.197.146:8984/solr: Error CREATEing SolrCore 'labs_shard1_replica1': Unable to create core [labs_shard1_replica1] Caused by: [solrconfig.xml] directoryFactory: missing mandatory attribute 'class'"}}

avatar

<directoryFactory name="DirectoryFactory"/>

I tried replacing with

<directoryFactory name="DirectoryFactory" class="solr.HdfsDirectoryFactory">

But that did not help got the same error

avatar

Sorry had to break up the comment because of 600 character limit

avatar

@Andrew Grande: thanks for the info!

@azeltov looks like there was a missing class attribute in step 2 where solrconfig.xml is modified. I have added it in and tested that it works.

<directoryFactory name="DirectoryFactory" class="solr.HdfsDirectoryFactory">
avatar

Thanks @Ali Bajwa ! Per our conversation, clean out the directories, stop solr, and if you got into bad state create the solr collection using a new name , that will do the trick

avatar
Master Mentor

thanks @azeltov and @Ali Bajwa the latest changes fixed the problem with this tutorial.

avatar
Getting the following error, Please help
  • labs_shard1_replica1: org.apache.solr.common.SolrException:org.apache.solr.common.SolrException: Index locked for write for core labs_shard1_replica1
  • labs_shard2_replica1: org.apache.solr.common.SolrException:org.apache.solr.common.SolrException: Index locked for write for core labs_shard2_replica1
avatar

@Saad Siddique check out this article https://community.hortonworks.com/articles/15159/securing-solr-collections-with-ranger-kerberos.html there is a section that covers the "Index locked for write" error.

Basically you have to remove the write.lock file from the index folder and restart your solr instances

Version history
Last update:
‎08-17-2019 02:04 PM
Updated by:
Contributors