nutch2.md

$ wget http://www-eu.apache.org/dist/nutch/2.3.1/apache-nutch-2.3.1-src.tar.gz
$ tar xvfz apache-nutch-2.3.1-src.tar.gz
$ cd apache-nutch-2.3.1/conf

$NUTCH_HOME/conf/nutch-site.xml

<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
 Licensed to the Apache Software Foundation (ASF) under one or more
 contributor license agreements.  See the NOTICE file distributed with
 this work for additional information regarding copyright ownership.
 The ASF licenses this file to You under the Apache License, Version 2.0
 (the "License"); you may not use this file except in compliance with
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     http://www.apache.org/licenses/LICENSE-2.0
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 distributed under the License is distributed on an "AS IS" BASIS,
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 See the License for the specific language governing permissions and
 limitations under the License.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>
<property>
     <name>http.agent.name</name>
     <value>nutch-2.3.1-crawler</value>
 </property>
 <property>
    <name>storage.data.store.class</name>
    <value>org.apache.gora.mongodb.store.MongoStore</value>
    <description>Default class for storing data</description>
</property>
 <property>
    <name>plugin.includes</name>
    <value>protocol-httpclient|urlfilter-regex|index-(basic|more)|query-(basic|site|url|lang)|indexer-solr|nutch-extensionpoints|protocol-httpclient|urlfilter-regex|parse-(text|html|msexcel|msword|mspowerpoint|pdf)|summary-basic|scoring-opic|urlnormalizer-(pass|regex|basic)protocol-http|urlfilter-regex|parse-(html|tika|metatags)|index-(basic|anchor|more|metadata)</value>
 </property>
<property>
 <name>db.ignore.external.links</name>
 <value>true</value>
</property>
<property>
 <name>db.ignore.external.links.mode</name>
 <value>byDomain</value>
</property>
</configuration>

$NUTCH_HOME/conf/gora.properties

############################
# MongoDBStore properties  #
############################
gora.datastore.default=org.apache.gora.mongodb.store.MongoStore
gora.mongodb.override_hadoop_configuration=false
gora.mongodb.mapping.file=/gora-mongodb-mapping.xml
gora.mongodb.servers=localhost:27017
gora.mongodb.db=nutchdb

$NUTCH_HOME/conf/ivy/ivy.xml

<!-- Uncomment this to use MongoDB as Gora backend. -->
<dependency org="org.apache.gora" name="gora-mongodb" rev="0.6.1" conf="*->default" />

Now we build Nutch. Install ant if it is not installed already.

sudo apt-get install ant

build Nutch from $NUTCH_HOME folder

$ pwd
/home/ubuntu/apache-nutch-2.3.1
$ ant runtime

Crawl and Index

$ cd ~/apache-nutch-2.3.1/
$ mkdir urls
$ vi urls/seeds.text

runtime/local/bin/nutch inject urls/
runtime/local/bin/nutch generate -topN 50