The configuration file found in the Elasticsearch config directory could previously have
.json extension. Only
elasticsearch.yml is now supported.
In previous versions of Elasticsearch, the configuration file was allowed to contain duplicate keys. For example:
node: name: my-node node attr: rack: my-rack
In Elasticsearch 6.0.0, this is no longer permitted. Instead, this must be specified in a single key as:
node: name: my-node attr: rack: my-rack
Previously, Elasticsearch recognized the strings
1 as booleans. Elasticsearch 6.0
false as boolean and will throw an error otherwise. For backwards compatibility purposes, during the 6.x series
index settings on pre-6.0 indices will continue to work. Note that this does not apply to node-level settings that are stored
The internal setting
cluster.routing.allocation.snapshot.relocation_enabled that allowed shards with running snapshots to be reallocated to
different nodes has been removed. Enabling this setting could cause allocation issues if a shard got allocated off a node and then
reallocated back to this node while a snapshot was running.
Store throttling has been removed. As a consequence, the
cluster settings and the
index.store.throttle.max_bytes_per_sec index settings are not
index.store.type has been removed. If you were using it, we
advise that you simply remove it from your index settings and Elasticsearch
will use the best
store implementation for your operating system.
The blocking TCP client, blocking TCP server, and blocking HTTP server have been removed.
As a consequence, the
http.tcp.blocking_server settings are not recognized anymore.
base similarity is now ignored as coords and query normalization have
been removed. If provided, this setting will be ignored and issue a
All of the existing scripting security settings have been removed. Instead
they are replaced with
discovery.type settings no longer supports the values
Integration with these platforms should be done by setting the
discovery.zen.hosts_provider setting to
one of those values.