As user-defined cluster metadata is accessible to anyone with access to
get the cluster settings, stored in the logs, and likely to be tracked
by monitoring solutions, it is useful to clarify in the documentation
that it should not be used to store secret information.
Adds a place for users to store cluster-wide data they wish to associate
with the cluster via the Cluster Settings API. This is strictly for
user-defined data, Elasticsearch makes no other other use of these
settings.
Control max size and count of warning headers
Add a static persistent cluster level setting
"http.max_warning_header_count" to control the maximum number of
warning headers in client HTTP responses.
Defaults to unbounded.
Add a static persistent cluster level setting
"http.max_warning_header_size" to control the maximum total size of
warning headers in client HTTP responses.
Defaults to unbounded.
With every warning header that exceeds these limits,
a message will be logged in the main ES log,
and any more warning headers for this response will be
ignored.
This commit adds a new setting `cluster.persistent_tasks.allocation.enable`
that can be used to enable or disable the allocation of persistent tasks.
The setting accepts the values `all` (default) or `none`. When set to
none, the persistent tasks that are created (or that must be reassigned)
won't be assigned to a node but will reside in the cluster state with
a no "executor node" and a reason describing why it is not assigned:
```
"assignment" : {
"executor_node" : null,
"explanation" : "persistent task [foo/bar] cannot be assigned [no
persistent task assignments are allowed due to cluster settings]"
}
```
Today when an index is `read-only` the index is also blocked from
being deleted which sometimes is undesired since in-order to make
changes to a cluster indices must be deleted to free up space. This is
a likely scenario in a hosted environment when disk-space is limited to switch
indices read-only but allow deletions to free up space.
* plugins/discovery-azure-class.asciidoc
* reference/cluster.asciidoc
* reference/modules/cluster/misc.asciidoc
* reference/modules/indices/request_cache.asciidoc
After this is merged there will be no unconvereted snippets outside
of `reference`.
Related to #18160
In 7560101ec7, the Elasticsearch logger
names were modified to be their fully-qualified class name (with some
exceptions for special loggers like the slow logs and the transport
tracer). This commit updates the docs accordingly.
Relates #20475
Gordon Brown
Mayya Sharipova
Tanguy Leroux
Simon Willnauer
Nik Everett
Jason Tedor
Ali Beyad
Clinton Gormley