getClusterParameter

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Definition
Syntax
Command Fields
Behavior
Examples

Definition

getClusterParameter

getClusterParameter is an administrative command for retrieving the values of cluster parameters. Cluster parameters are configurable parameters that affect all nodes in a sharded cluster.

To run getClusterParameter, use the db.adminCommand( { command } ) method.

The getClusterParameter command is only available in self-managed installations. The getClusterParameter command is not available in MongoDB Atlas.

Syntax

The command has the following syntax:

db.adminCommand(
   {
     getClusterParameter: <parameter> | [<parameter>, <parameter>] | "'*'"
   }
)

Command Fields

The command takes the following fields:

Field	Type	Description
`<parameter>`	String or array of strings	You can specify one of the following: The name of the parameter you want to retrieve. An array with the names of multiple parameters. `'*'`, to return values for all parameters available to `getClusterParameter`.

Behavior

You can only run getClusterParameter on the admin database. If you run the command on any other database, MongoDB returns an error.
You can run getClusterParameter on any node in a replica set or sharded cluster.
When you run getClusterParameter on mongod, getClusterParameter returns cached parameter values.
When you run getClusterParameter on mongos, getClusterParameter returns the durable value of the cluster parameter from the config server.

Access Control

When authentication is enabled, getClusterParameter only works when authenticated as a user with a role that has access to the getClusterParameter action.

Examples

Note

The output of the following examples may vary depending on the specific configuration of the running MongoDB deployment.

Retrieve Single Cluster Parameter

The following operation runs getClusterParameter on the admin database using a value of hostName to retrieve the value for a hypothetical cluster parameter named hostName:

use admin
db.adminCommand( { getClusterParameter : "hostName" } )

Retrieve Multiple Cluster Parameters

The following operation runs getClusterParameter on the admin database using the values hostName and testParameter to retrieve the values for hypothetical cluster parameters named hostName and testParameter:

use admin
db.adminCommand( { getClusterParameter: [ "hostName", "testParameter" ] } )

Retrieve All Cluster Parameters

The following operation runs getClusterParameter with a value of '*' to retrieve the values from all cluster parameters:

use admin
db.adminCommand( { getClusterParameter : '*' } )

Tip