Product release

Elasticsearch 5.0.0-rc1 released

Today we are on the edge of our seats with excitement, because we’re announcing the release of Elasticsearch 5.0.0-rc1 based on Lucene 6.2.0. This means that the GA release is VERY VERY CLOSE! This is the seventh in a series of pre-5.0.0 releases designed to let you test out your application with the features and changes coming in 5.0.0, and to give us feedback about any problems that you encounter.

Open a bug report today and become an Elastic Pioneer.

IMPORTANT: This is an RC release and is intended for testing purposes only.


This release contains a number of minor enhancements and bug fixes that have been added since 5.0.0-alpha5 (all of which you can read about in the release notes linked above), and one big change: strict URL query-string parameter parsing.

Strict URL query-string parameter parsing

While working on 5.0, we have adopted a "shout early, should loud" approach. If your nodes don’t have enough file handles, throw an exception and fail. If you have an unknown setting or an invalid value for a setting, throw an exception and fail. Unknown or incorrect mappings, invalid search requests? Throw an exception and fail!

It is so much easier to find and fix a problem when you know that it is a problem!

Continuing in this vein, parsing of URL query-string parameters is now strict. No more silently ignoring unknown or mistyped options. Take this for example:

POST _analyze?analyser=whitespace
{ "text": "Whitespace-only splitting" }

How long would you need to stare at that to figure out why the whitespace analyzer isn’t being applied correctly? It’s so much easier when you get this response instead:

request [/_analyze] contains unrecognized parameter: [analyser] -> did you mean [analyzer]?

And what do you know? Turns out we were using invalid query string parameters in our projects too.

Migration Helper

The Elasticsearch Migration Helper is a site plugin designed to help you to prepare for your migration from Elasticsearch 2.3.x/2.4.x to Elasticsearch 5.0. It comes with three tools:

Cluster Checkup
Runs a series of checks on your cluster, nodes, and indices and alerts you to any known problems that need to be rectified before upgrading.
Reindex Helper
Indices created before v2.0.0 need to be reindexed before they can be used in Elasticsearch 5.x. The reindex helper upgrades old indices at the click of a button.
Deprecation Logging
Elasticsearch comes with a deprecation logger which will log a message whenever deprecated functionality is used. This tool enables or disables deprecation logging on your cluster.

Instruction for install the Elasticsearch migration helper.


Also take a look at the release announcements for Elasticsearch 5.0.0-beta1, Elasticsearch 5.0.0-alpha5, Elasticsearch 5.0.0-alpha4, Elasticsearch 5.0.0-alpha3, Elasticsearch 5.0.0-alpha2, and Elasticsearch 5.0.0-alpha1 to read about features like:

  • Indexing performance improvements
  • Geo-point queries double the speed
  • Sysadmin-friendly index creation
  • Netty4
  • Java REST client
  • Rollover indexing
  • Wait for refresh
  • Ingest Node
  • Painless - the new default scripting language
  • Instant Aggregations
  • Text/Keyword fields replacing String
  • Completion Suggester v2
  • Settings Validation
  • Safety in Production
  • Resiliency Improvements
  • Percolate Query
  • Deleted Index Tombstones
  • Dots in field names
  • Cluster allocation explain API

Please download Elasticsearch 5.0.0-rc1, try it out, and let us know what you think on Twitter (@elastic) or in our forum. You can report any problems on the GitHub issues page.