Srikanth Jeeva's technical Blog

I have followed these steps in order to setup Elastic search in production. # OS Requirements: Centos 6+ & Java 1.8+ Step1: ------ ------ Installing Java --------------- Download JDK from : http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html tar xzvf jdk.tar.gz sudo mkdir /usr/local/java sudo mv jdk1.8.0_45 /usr/local/java/ sudo ln -s /usr/local/java/jdk1.8.0_45 /usr/local/java/jdk export PATH="$PATH:/usr/local/java/jdk/bin" export JAVA_HOME=/usr/local/java/jdk1.8.0_91/jre sudo sh -c "echo export JAVA_HOME=/usr/local/java/jdk1.8.0_91/jre >> /etc/environment" Step2: ----- ----- Installing Elasticsearch ------------------------ wget https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.3.3/elasticsearch-2.3.3.rpm sudo rpm -ivh elasticsearch-2.3.3.rpm Step 3: ------- ------- Configure Elasticsearch ----------------------- sudo vi /etc/elasticsearch/elasticsearch...

Elastic search will index every field and every word within a value. For Example: Document 1 has : "text": "Hello World" Document 2 has : "text": "Hello Srikanth" ElasticSearch by default will create many indexes and in that the 3 index would be, ["Hello", "World", "Srikanth"] In some case we want to disable the Full text search, So that we can aggregate by that value. For Example: Document 1 has : "filepath": "/home/srikanth/1.c" Document 2 has : "filepath": "/home/srikanth/2.c" By default, ElasticSearch will index these documents by ["home", "srikanth, ".c"] , So at the time of aggregating with the path, these values will mess up the aggregated document count. So we have to tell ElasticSearch, not to index the data by By this we tell ElasticSearch, that we will always search by the full string and not by sub-strings.

Sometimes while making heavy calculations it is possible that node.js runs out of memory and throws this error " FATAL ERROR- JS Allocation failed – process out of memory"   By default node.js occupies 512MB RAM in a 32 bit machine and 1.4GB RAM in a 64bit machine This is how we can increase it.