Today, we are pleased to announce bug fix releases of Elasticsearch 1.7.1 based on Lucene 4.10.4, and Elasticsearch 1.6.2. These releases contain a fix for a rarely occurring but important bug which can cause data loss. All users are advised to upgrade.
You can download them and read the full changes list here:
The bug in question (#12487) can, in very rare circumstances involving multiple simultaneous node failures or restarts, cause all copies of a shard to be deleted from the cluster. This bug was introduced in 1.5.0.
This release also contains a fix for CIDR mask conversion for IPv4 addresses, and a bug that prevented Shield users from using the more-like-this API, plus a few more changes whose details can be found in the changes list.