Generally, we strive to maintain backwards compatibility between minor versions (e.g. 5.x to 5.7) so that upgrades can be done without any code or configuration changes, but breaking changes do manifest between major versions (e.g. 5.x to 6.y).
For clarity, we always list any breaking changes at the top of the release notes for each version.
This section discusses the changes that you should be aware of if you upgrade Elasticsearch from version 5.4 to 5.5.
In 5.5, Elasticsearch has removed a deprecated way of checking the existance of types. ES-Hadoop was previously using this deprecated endpoint up until the 5.4.x releases. If you have upgraded to Elasticsearch 5.5.0, you will need to upgrade ES-Hadoop to version 5.5.0.
This section discusses the changes that you should be aware of if you upgrade ES-Hadoop from version 2.x to 5.x.
ES-Hadoop 5.0 has added support for new versions of software from the Hadoop ecosystem. Support for older versions is normally dropped during these cycles for the purposes of stability and to allow for cleanup of older code. Please note the following version compatibility changes in 5.0:
- Support for Hive 0.13 and 0.14 has been removed. These versions of Hive are known to have serious issues that have since been repaired in 1.0. Hive 1.0 has been released for a while and a majority of distributions have already switched to it. Hive 1.0 will continue to be supported by ES-Hadoop 5.0.
- With the addition of support for Storm 1.x, support for Storm 0.9 has been removed due to backwards compatibility issues.
- Support for SparkSQL 1.0-1.2 has been removed. SparkSQL was originally released in Spark 1.0-1.2 as an alpha, but has since become stable in Spark 1.3 with a drastically changed API. Additionally, we have added support for Spark 2.0, which is binary-incompatible with previous versions of Spark. Instead of supporting three different version compatibilities of Spark at the same time we have decided to drop support for Spark SQL 1.0-1.2.
With the removal of support for Spark 1.0-1.2 and the addition of support for Spark 2.0, the names of all the Spark artifacts included in ES-Hadoop 5.0 have changed. All Spark artifacts in this release now have both of their Spark and Scala versions explicitly demarcated in their names (instead of just Scala and sometimes Spark).
Table C.1. Spark Jar Name Changes from 2.x to 5.x
|Spark Version||Scala Version||ES-Hadoop 2.x name||ES-Hadoop 5.x Name|
1.0 - 1.2
1.0 - 1.2
1.3 - 1.6
1.3 - 1.6
In 5.0, the HDFS Repository plugin has been all but re-built from the ground up to allow for compatibility with the changes to security policies in Elasticsearch’s plugin framework.
Disabling the Java SecurityManager in Elasticsearch is no longer required for the HDFS Repository plugin to function. Elasticsearch 5.0 requires all plugins to operate properly with the configured SecurityManager. The plugin was heavily modified to allow for compatibility with this new constraint. This should allow you to maintain a secured Elasticsearch instance while still using HDFS as a location for storing snapshots.
Due to constraints in the underlying security system as well as changes to the way the plugin functions, the following configurations have been removed in 5.0 with no replacement options:
Previously, the HDFS Repository supported both Apache Hadoop 1.x (default) and Apache Hadoop 2.x through two distributions. In 5.0, there is now only one distribution which is built against the latest Apache Hadoop 2.x (at this time 2.7.1). The distribution for Apache Hadoop 1.x has been removed.
Even if Hadoop is already installed on the Elasticsearch nodes, for security
reasons, the required libraries need to be placed under the plugin folder.
Because of this, the
light distribution of the repository plugin which
contained no Hadoop client dependencies is no longer available in 5.0.
In previous versions, users were able to specify options that modify search
properties in Query DSL strings provided to the client. In some cases these
properties would conflict with how the framework executed searches during
read operations. In 5.0, when specifying a Query DSL string, if a
is present, its contents are extracted and all other contents are discarded
size). If there is no
query field, the entire text
is nested inside of the
query field during execution.