Lukáš Vlček 98c7dd29a6 Fixing Nodes APIs issues
1. Fixing all reported dead links.
2. Changing `title` value in index.md back to plural form, i.e. "Nodes APIs".

The second change fixed missing child pages. I am not saying I insist on use of plural form but if we want to change it to a singular form then we also have to change `parent` fields in all child pages to correctly refer to valid parent, otherwise all child pages and content is missing.

As for the debate of use APIs vs API (plural vs singular) I just want to point out that right now there are many other parent pages using plural form. If we want to change that then I suggest doing it in separate PR and include other relevant parent pages too.

Closes: #591
Signed-off-by: Lukáš Vlček <lukas.vlcek@aiven.io>
2022-05-20 11:36:23 +02:00

2.3 KiB

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default Nodes APIs REST API reference true 5

Nodes API

The nodes API makes it possible to retrieve information about individual nodes within your cluster. It supports standard parameters such {timeout} and {node-filters}.

Timeout

The {timeout} parameter can be used to change the default time limit for node response.

Parameter Type Description
{timeout} TimeValue Default value is 30s.

Node filters

Use the {node-filters} parameter to filter the target set of nodes in the API response.

Parameter Type Description
{node-filters} String A comma-separated list of resolution mechanisms that OpenSearch uses to identify cluster nodes.

Node filters support several node resolution mechanisms.

  • Pre defined constants: _local, _cluster_manager, or _all
  • An exact match for nodeID
  • A simple case-sensitive wildcard pattern matching for node-name, host-name, or host-IP-address
  • Node roles where the <bool> value is set either to true or false):
    • cluster_manager:<bool>
    • data:<bool>
    • ingest:<bool>
    • voting_only:<bool>
    • ml:<bool>
    • coordinating_only:<bool>
  • A simple case-sensitive wildcard pattern matching for node attributes: <node attribute*>:<attribute value*>. The wildcard matching pattern can be used in both the key and value at the same time.

Resolution mechanisms are applied sequentially in the order specified by the client. Each mechanism specification can either add or remove nodes.

If you want to get statistics from the elected cluster manager node only, use the following:

GET /_nodes/_cluster_manager/stats

If you want to get statistics from nodes that are data-only nodes, use the following:

GET /_nodes/data:true/stats

Order of resolution mechanisms

The order of resolution mechanisms is applied sequentially, and each can add or remove nodes. The following examples yield different results:

If you want to get statistics from all the nodes but the cluster manager node, use the following:

GET /_nodes/_all,cluster_manager:false/stats

However, if we switch the resolution mechanisms, then the result will include all the cluster nodes including the cluster manager node.

GET /_nodes/cluster_namager:false,_all/stats