You're viewing version 2.6 of the OpenSearch documentation. This version is no longer maintained. For the latest version, see the current documentation. For information about OpenSearch version maintenance, see Release Schedule and Maintenance Policy.
Nodes info
The nodes info API represents mostly static information about your cluster’s nodes, including but not limited to:
- Host system information
- JVM
- Processor Type
- Node settings
- Thread pools settings
- Installed plugins
Example
To get information about all nodes in a cluster, use the following query:
GET /_nodes
To get thread pool information about the cluster manager node only, use the following query:
GET /_nodes/master:true/thread_pool
Path and HTTP methods
GET /_nodes
GET /_nodes/<nodeId>
GET /_nodes/<metrics>
GET /_nodes/<nodeId>/<metrics>
# or full path equivalent
GET /_nodes/<nodeId>/info/<metrics>
Path parameters
The following table lists the available path parameters. All path parameters are optional.
| Parameter | Type | Description |
|---|---|---|
| nodeId | String | A comma-separated list of nodeIds used to filter results. Supports node filters. Defaults to _all. |
| metrics | String | A comma-separated list of metric groups that will be included in the response. For example, jvm,thread_pool. Defaults to all metrics. |
The following table lists all available metric groups.
| Metric | Description |
|---|---|
| settings | A node’s settings. This is a combination of the default settings, custom settings from the configuration file, and dynamically updated settings. |
| os | Static information about the host OS, including version, processor architecture, and available/allocated processors. |
| process | Contains the process ID. |
| jvm | Detailed static information about the running JVM, including arguments. |
| thread_pool | Configured options for all individual thread pools. |
| transport | Mostly static information about the transport layer. |
| http | Mostly static information about the HTTP layer. |
| plugins | Information about installed plugins and modules. |
| ingest | Information about ingest pipelines and available ingest processors. |
| aggregations | Information about available aggregations. |
| indices | Static index settings configured at the node level. |
Query parameters
You can include the following query parameters in your request. All query parameters are optional.
| Parameter | Type | Description |
|---|---|---|
| flat_settings | Boolean | Specifies whether to return the settings object of the response in flat format. Default is false. |
| timeout | Time | Sets the time limit for node response. Default value is 30s. |
Example request
The following query requests the process and transport metrics from the cluster manager node:
GET /_nodes/cluster_manager:true/process,transport
Example response
The response contains the metric groups specified in the <metrics> request parameter (in this case, process and transport):
{
"_nodes": {
"total": 1,
"successful": 1,
"failed": 0
},
"cluster_name": "opensearch",
"nodes": {
"VC0d4RgbTM6kLDwuud2XZQ": {
"name": "node-m1-23",
"transport_address": "127.0.0.1:9300",
"host": "127.0.0.1",
"ip": "127.0.0.1",
"version": "1.3.1",
"build_type": "tar",
"build_hash": "c4c0672877bf0f787ca857c7c37b775967f93d81",
"roles": [
"data",
"ingest",
"master",
"remote_cluster_client"
],
"attributes": {
"shard_indexing_pressure_enabled": "true"
},
"process" : {
"refresh_interval_in_millis": 1000,
"id": 44584,
"mlockall": false
},
"transport": {
"bound_address": [
"[::1]:9300",
"127.0.0.1:9300"
],
"publish_address": "127.0.0.1:9300",
"profiles": { }
}
}
}
}
Response fields
The response contains the basic node identification and build info for every node matching the <nodeId> request parameter. The following table lists the response fields.
| Field | Description |
|---|---|
| name | The node’s name. |
| transport_address | The node’s transport address. |
| host | The node’s host address. |
| ip | The node’s host IP address. |
| version | The node’s OpenSearch version. |
| build_type | The node’s build type, like rpm, docker, tar, etc. |
| build_hash | The git commit hash of the build. |
| total_indexing_buffer | The maximum heap size in bytes used to hold newly indexed documents. Once this heap size is exceeded, the documents are written to disk. |
| roles | The list of the node’s roles. |
| attributes | The node’s attributes. |
| os | Information about the OS, including name, version, architecture, refresh interval, and the number of available and allocated processors. |
| process | Information about the currently running process, including PID, refresh interval, and mlockall, which specifies whether the process address space has been successfully locked in memory. |
| jvm | Information about the JVM, including PID, version, memory information, garbage collector information, and arguments. |
| thread_pool | Information about the thread pool. |
| transport | Information about the transport address, including bound address, publish address, and profiles. |
| http | Information about the HTTP address, including bound address, publish address, and maximum content length, in bytes. |
| plugins | Information about the installed plugins, including name, version, OpenSearch version, Java version, description, class name, custom folder name, a list of extended plugins, and has_native_controller, which specifies whether the plugin has a native controller process. |
| modules | Information about the modules, including name, version, OpenSearch version, Java version, description, class name, custom folder name, a list of extended plugins, and has_native_controller, which specifies whether the plugin has a native controller process. Modules are different from plugins because modules are loaded into OpenSearch automatically, while plugins have to be installed manually. |
| ingest | Information about ingest pipelines and processors. |
| aggregations | Information about the available aggregation types. |
Required permissions
If you use the Security plugin, make sure you have the appropriate permissions: cluster:monitor/nodes/info.