Issues faced during ES upgrade from 1.4.2 to 2.3.2

Not yet.

You should use Maven or Gradle to get the dependencies.

Here we go:

$ mvn dependency:tree
[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building Elasticsearch: Core 2.3.4-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ elasticsearch ---
[INFO] org.elasticsearch:elasticsearch:jar:2.3.4-SNAPSHOT
[INFO] +- org.hamcrest:hamcrest-all:jar:1.3:test
[INFO] +- com.carrotsearch.randomizedtesting:randomizedtesting-runner:jar:2.3.2:test
[INFO] |  \- junit:junit:jar:4.11:test
[INFO] +- org.apache.lucene:lucene-test-framework:jar:5.5.0:test
[INFO] |  \- org.apache.lucene:lucene-codecs:jar:5.5.0:test
[INFO] +- org.apache.httpcomponents:httpclient:jar:4.3.6:test
[INFO] |  +- org.apache.httpcomponents:httpcore:jar:4.3.3:test
[INFO] |  +- commons-logging:commons-logging:jar:1.1.3:test
[INFO] |  \- commons-codec:commons-codec:jar:1.6:test
[INFO] +- com.google.jimfs:jimfs:jar:1.0:test
[INFO] +- org.apache.lucene:lucene-core:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-backward-codecs:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-analyzers-common:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-queries:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-memory:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-highlighter:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-queryparser:jar:5.5.0:compile
[INFO] |  \- org.apache.lucene:lucene-sandbox:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-suggest:jar:5.5.0:compile
[INFO] |  \- org.apache.lucene:lucene-misc:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-join:jar:5.5.0:compile
[INFO] |  \- org.apache.lucene:lucene-grouping:jar:5.5.0:compile
[INFO] +- org.apache.lucene:lucene-spatial:jar:5.5.0:compile
[INFO] |  \- org.apache.lucene:lucene-spatial3d:jar:5.5.0:compile
[INFO] +- com.spatial4j:spatial4j:jar:0.5:compile
[INFO] +- com.vividsolutions:jts:jar:1.13:compile
[INFO] +- com.github.spullara.mustache.java:compiler:jar:0.8.13:compile
[INFO] +- com.google.guava:guava:jar:18.0:compile
[INFO] +- org.elasticsearch:securesm:jar:1.0:compile
[INFO] +- com.carrotsearch:hppc:jar:0.7.1:compile
[INFO] +- joda-time:joda-time:jar:2.9.4:compile
[INFO] +- org.joda:joda-convert:jar:1.2:compile
[INFO] +- com.fasterxml.jackson.core:jackson-core:jar:2.6.6:compile
[INFO] +- com.fasterxml.jackson.dataformat:jackson-dataformat-smile:jar:2.6.6:compile
[INFO] +- com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:jar:2.6.6:compile
[INFO] |  \- org.yaml:snakeyaml:jar:1.15:compile
[INFO] +- com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:jar:2.6.6:compile
[INFO] +- io.netty:netty:jar:3.10.5.Final:compile
[INFO] +- com.ning:compress-lzf:jar:1.0.2:compile
[INFO] +- com.tdunning:t-digest:jar:3.0:compile
[INFO] +- org.hdrhistogram:HdrHistogram:jar:2.1.6:compile
[INFO] +- commons-cli:commons-cli:jar:1.3.1:compile
[INFO] +- log4j:log4j:jar:1.2.17:compile
[INFO] +- log4j:apache-log4j-extras:jar:1.2.17:compile
[INFO] +- org.slf4j:slf4j-api:jar:1.6.2:compile
[INFO] +- net.java.dev.jna:jna:jar:4.1.0:compile
[INFO] \- com.twitter:jsr166e:jar:1.1.0:compile

If you want to be able to access elasticsearch from another machine, you'll have to define network.host.

HTH