A voting-only master-eligible node is a node that can participate in master elections but will not act
as a master in the cluster. In particular, a voting-only node can help elect another master-eligible
node as master, and can serve as a tiebreaker in elections. High availability (HA) clusters require at
least three master-eligible nodes, so that if one of the three nodes is down, then the remaining two
can still elect a master amongst them-selves. This only requires one of the two remaining nodes to
have the capability to act as master, but both need to have voting powers. This means that one of
the three master-eligible nodes can be made as voting-only. If this voting-only node is a dedicated
master, a less powerful machine or a smaller heap-size can be chosen for this node. Alternatively, a
voting-only non-dedicated master node can play the role of the third master-eligible node, which
allows running an HA cluster with only two dedicated master nodes.
Closes#14340
Co-authored-by: David Turner <david.turner@elastic.co>
The `GET /_cluster/state` API returns an internal representation of the cluster
state that does change from version to version. It's useful for debugging, but
it is not intended for regular use by clients.
This change adjusts the documentation of `GET /_cluster/state` to clarify that
this API yields an internal representation that should not be expected to
remain stable between versions.
Relates #40061, #40016
This fixes a bug in the sensing of the current OS family in the test cluster
formation code. Previously all builds would assume every environment
was windows and would jump to using the windows zip build. This fixes
the OS sensing code as well as updates some tests to account for
different build flavors.
Backport of #38457
Today our OS information returned in node stats only returns a
high-level name of the OS (e.g., "Linux"). Yet, for some uses this is
too high-level and knowing at a finer level of granularity the
underlying OS can be useful. This commit extracts the pretty name on
Linux from /etc/os-release. This pretty name usually includes the Linux
vendor and the Linux vendor version number (e.g., Fedora 28).
The `status` part of the tasks API reflects the internal status of a
running task. In general, we do not make backwards breaking changes to
the `status` but because it is internal we reserve the right to do so. I
suspect we will very rarely excercise that right but it is important
that we have it so we're not boxed into any particular implementation
for a request.
In some sense this is policy making by documentation change. In another
it is clarification of the way we've always thought of this field.
I also reflect the documentation change into the Javadoc in a few
places. There I acknowledge Kibana's "special relationship" with
Elasticsearch. Kibana parses `_reindex`'s `status` field and, because
we're friends with those folks, we should talk to them before we make
backwards breaking changes to it. We *want* to be friends with everyone
but there is only so much time in the day and we don't *want* to make
backwards breaking fields to `status` at all anyway. So we hope that
breaking changes documentation should be enough for other folks.
Relates to #34245.
Expands and clarifies exactly what is and isn't allowed when specifying a
subset of the nodes as targets of a cluster API, and adds missing links to this
from the hot threads and cluster stats API docs.
Co-authored-by: David Turner <david.turner@elastic.co>
Co-authored-by: Yu <yu.liu003@gmail.com>
* Make cluster stats response contain cluster UUID
* Updating constructor usage in Monitoring tests
* Adding cluster_uuid field to Cluster Stats API reference doc
* Adding rest api spec test for expecting cluster_uuid in cluster stats response
* Adding missing newline
* Indenting do section properly
* Missed a spot!
* Fixing the test cluster ID
This switches the docs tests from the `oss-zip` distribution to the
`zip` distribution so they have xpack installed and configured with the
default basic license. The goal is to be able to merge the
`x-pack/docs` directory into the `docs` directory, marking the x-pack
docs with some kind of marker. This is the first step in that process.
This also enables `-Dtests.distribution` support for the `docs`
directory so you can run the tests against the `oss-zip` distribution
with something like
```
./gradlew -p docs check -Dtests.distribution=oss-zip
```
We can set up Jenkins to run both.
Relates to #30665
This commit changes the default out-of-the-box configuration for the
number of shards from five to one. We think this will help address a
common problem of oversharding. For users with time-based indices that
need a different default, this can be managed with index templates. For
users with non-time-based indices that find they need to re-shard with
the split API in place they no longer need to resort only to
reindexing.
Since this has the impact of changing the default number of shards used
in REST tests, we want to ensure that we still have coverage for issues
that could arise from multiple shards. As such, we randomize (rarely)
the default number of shards in REST tests to two. This is managed via a
global index template. However, some tests check the templates that are
in the cluster state during the test. Since this template is randomly
there, we need a way for tests to skip adding the template used to set
the number of shards to two. For this we add the default_shards feature
skip. To avoid having to write our docs in a complicated way because
sometimes they might be behind one shard, and sometimes they might be
behind two shards we apply the default_shards feature skip to all docs
tests. That is, these tests will always run with the default number of
shards (one).
We had been using `task_id:1` or `taskId:1` because it is parses as a
valid task identifier but the `:1` part is confusing. This replaces
those examples with `task_id` which matches the response from the list
tasks API.
Closes#28314
Currently, the only way to get the REST response for the `/_cluster/state`
call to return the `cluster_uuid` is to request the `metadata` metrics,
which is one of the most expensive response structures. However, external
monitoring agents will likely want the `cluster_uuid` to correlate the
response with other API responses whether or not they want cluster
metadata.
Add yet another warning about data loss to the introductory paragraph about the
unsafe commands. Also move this paragraph next to the details of the unsafe
commands, below the section on the `retry_failed` flag.
Be more specific about how to use the URI parameters and in-body flags.
Clarify statements about when rebalancing takes place (i.e. it respects
settings)
Resolves#16113.
This commit adds the distribution type to the startup scripts so that we
can discern from log output and the main response the type of the
distribution (deb/rpm/tar/zip).
The suggest stats were folded into the search stats as part of the
indices stats API in 5.0.0. However, the suggest metric remained as a
synonym for the search metric for BWC reasons. This commit deprecates
usage of the suggest metric on the indices stats API.
Similarly, due to the changes to fold the suggest stats into the search
stats, requesting the suggest index metric on the indices metric on the
nodes stats API has produced an empty object as the response since
5.0.0. This commit deprecates this index metric on the indices metric on
the nodes stats API.
The node stats API enables filtlering the top-level stats for only
desired top-level stats. Yet, this was never enabled for adaptive
replica selection stats. This commit enables this. We also add setting
these stats on the request builder, and fix an inconsistent name in a
setter.
Relates #28721
#27611 broke the docs tests because $node_name in the URL doesn't (#27616)seem to be replaced.
Changing this to a * to match all nodes seems to fix the test
Today Cross Cluster Search requires at least one node in each remote cluster to be up once the cross cluster search is run. Otherwise the whole search request fails despite some of the data (either local and/or remote) is available. This happens when performing the _search/shards calls to find out which remote shards the query has to be executed on. This scenario is different from shard failures that may happen later on when the query is actually executed, in case e.g. remote shards are missing, which is not going to fail the whole request but rather yield partial results, and the _shards section in the response will indicate that.
This commit introduces a boolean setting per cluster called search.remote.$cluster_alias.skip_if_disconnected, set to false by default, which allows to skip certain clusters if they are down when trying to reach them through a cross cluster search requests. By default all clusters are mandatory.
Scroll requests support such setting too when they are first initiated (first search request with scroll parameter), but subsequent scroll rounds (_search/scroll endpoint) will fail if some of the remote clusters went down meanwhile.
The search API response contains now a new _clusters section, similar to the _shards section, that gets returned whenever one or more clusters were disconnected and got skipped:
"_clusters" : {
"total" : 3,
"successful" : 2,
"skipped" : 1
}
Such section won't be part of the response if no clusters have been skipped.
The per cluster skip_unavailable setting value has also been added to the output of the remote/info API.
This change adds cgroup memory usage/limit to the OS stats section of
the node stats on Linux. This information is useful because in Docker
containers the standard node stats report the host memory limit, not
taking account of extra restrictions that may have been applied to the
container.
The original idea was to store these values as Long, truncating any values
outside the range of long. However, this meant that in the relatively common
case of no limit being applied, users would not see the same value in the OS
stats as they see by querying Linux directly. So instead the values are stored
as String. This change places a burden on consumers of the strings to
convert the strings to numbers and decide what to do about extremely large
values, but there will be very few consumers and they would need to have a
policy for dealing with "no limit" in any case.
This commit removes an outdated reference to http_address in the nodes
info docs. This information is available in the http object for each
node in the nodes info API response.
Relates #25980
The example output for node info and cluster stats was outdated w.r.t.
to the information that is shown for plugins. With this commit we
updated the example output and update the explanation of the respective
fields.
Yannick Welsch
Alpar Torok
Jason Tedor
David Turner
Lisa Cawley
James Baiera
Josh Soref
Ken MacInnis
Nik Everett
Christoph Büscher
lipsill
Albert Zaharovits
Sergey
Yu
Shaunak Kashyap
mzbeck
Sohaib Iftikhar
Van0SS
Chris Earle
Boaz Leskes
Igor Motov
Sandeep Kanabar
Clinton Gormley
佛陀.RML
Nhat Nguyen
Luca Cavanna
David Roberts
Peter Dyson
Tanguy Leroux
Daniel Mitterdorfer