71 lines
2.3 KiB
Markdown
71 lines
2.3 KiB
Markdown
---
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layout: default
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title: Nodes APIs
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parent: REST API reference
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has_children: true
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nav_order: 5
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---
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# Nodes API
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The nodes API makes it possible to retrieve information about individual nodes within your cluster. It supports standard parameters such `{timeout}` and `{node-filters}`.
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## Timeout
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The `{timeout}` parameter can be used to change the default time limit for node response.
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Parameter | Type | Description
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:--- |:----------| :---
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`{timeout}` | TimeValue | Default value is `30s`.
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## Node filters
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Use the `{node-filters}` parameter to filter the target set of nodes in the API response.
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Parameter | Type | Description
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:--- |:-------| :---
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{node-filters} | String | A comma-separated list of resolution mechanisms that OpenSearch uses to identify cluster nodes.
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Node filters support several node resolution mechanisms.
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- Pre defined constants: `_local`, `_cluster_manager`, or `_all`
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- An exact match for `nodeID`
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- A simple case-sensitive wildcard pattern matching for `node-name`, `host-name`, or `host-IP-address`
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- Node roles where the `<bool>` value is set either to `true` or `false`):
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- `cluster_manager:<bool>`
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- `data:<bool>`
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- `ingest:<bool>`
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- `voting_only:<bool>`
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- `ml:<bool>`
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- `coordinating_only:<bool>`
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- 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.
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Resolution mechanisms are applied sequentially in the order specified by the client. Each mechanism specification can either add or remove nodes.
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If you want to get statistics from the elected cluster manager node only, use the following:
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```bash
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GET /_nodes/_cluster_manager/stats
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```
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If you want to get statistics from nodes that are data-only nodes, use the following:
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```bash
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GET /_nodes/data:true/stats
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```
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### Order of resolution mechanisms
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The order of resolution mechanisms is applied sequentially, and each can add or remove nodes. The following examples yield different results:
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If you want to get statistics from all the nodes but the cluster manager node, use the following:
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```bash
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GET /_nodes/_all,cluster_manager:false/stats
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```
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However, if we switch the resolution mechanisms, then the result will include all the cluster nodes including the cluster manager node.
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```bash
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GET /_nodes/cluster_namager:false,_all/stats
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``` |