End of support notice: On October 7th, 2026, AWS will discontinue support for AWS IoT Greengrass Version 1. After October 7th, 2026, you will no longer be able to access the AWS IoT Greengrass V1 resources. For more information, please visit [Migrate from AWS IoT Greengrass Version 1](https://docs.aws.amazon.com/greengrass/v2/developerguide/migrate-from-v1.html).
# Configure AWS IoT Greengrass stream manager
On the AWS IoT Greengrass core, stream manager can store, process, and export IoT device data. Stream manager provides parameters that you use to configure group-level runtime settings. These settings apply to all streams on the Greengrass core. You can use the AWS IoT console or AWS IoT Greengrass API to configure stream manager settings. Changes take effect after the group is deployed.
**Note**
After you configure stream manager, you can create and deploy IoT applications that run on the Greengrass core and interact with stream manager. These IoT applications are typically user-defined Lambda functions. For more information, see [Use StreamManagerClient to work with streams](work-with-streams.md).
## Stream manager parameters
Stream manager provides the following parameters that allow you to define group-level settings. All parameters are optional.
**Storage directory**
Parameter name: `STREAM_MANAGER_STORE_ROOT_DIR`
The absolute path of the local directory used to store streams. This value must start with a forward slash (for example, `/data`).
For information about securing stream data, see [Local data security](stream-manager.md#stream-manager-security-stream-data).
Minimum AWS IoT Greengrass Core version: 1.10.0
**Server port**
Parameter name: `STREAM_MANAGER_SERVER_PORT`
The local port number used to communicate with stream manager. The default is `8088`.
Minimum AWS IoT Greengrass Core version: 1.10.0
**Authenticate client**
Parameter name: `STREAM_MANAGER_AUTHENTICATE_CLIENT`
Indicates whether clients must be authenticated to interact with stream manager. All interaction between clients and stream manager is controlled by the AWS IoT Greengrass Core SDK. This parameter determines which clients can call the AWS IoT Greengrass Core SDK to work with streams. For more information, see [Client authentication](stream-manager.md#stream-manager-security-client-authentication).
Valid values are `true` or `false`. The default is `true` (recommended).
+ `true`. Allows only Greengrass Lambda functions as clients. Lambda function clients use internal AWS IoT Greengrass core protocols to authenticate with the AWS IoT Greengrass Core SDK.
+ `false`. Allows any process that runs on the AWS IoT Greengrass core to be a client. Do not set to `false` unless your business case requires it. For example, set this value to `false` only if non-Lambda processes on the core device must communicate directly with stream manager, such as [Docker containers](docker-app-connector.md) running on the core.
Minimum AWS IoT Greengrass Core version: 1.10.0
**Maximum bandwidth**
Parameter name: `STREAM_MANAGER_EXPORTER_MAX_BANDWIDTH`
The average maximum bandwidth (in kilobits per second) that can be used to export data. The default allows unlimited use of available bandwidth.
Minimum AWS IoT Greengrass Core version: 1.10.0
**Thread pool size**
Parameter name: `STREAM_MANAGER_EXPORTER_THREAD_POOL_SIZE`
The maximum number of active threads that can be used to export data. The default is `5`.
The optimal size depends on your hardware, stream volume, and planned number of export streams. If your export speed is slow, you can adjust this setting to find the optimal size for your hardware and business case. The CPU and memory of your core device hardware are limiting factors. To start, you might try setting this value equal to the number of processor cores on the device.
Be careful not to set a size that's higher than your hardware can support. Each stream consumes hardware resources, so you should try to limit the number of export streams on constrained devices.
Minimum AWS IoT Greengrass Core version: 1.10.0
**JVM arguments**
Parameter name: `JVM_ARGS`
Custom Java Virtual Machine arguments to pass to stream manager at startup. Multiple arguments should be separated by spaces.
Use this parameter only when you must override the default settings used by the JVM. For example, you might need to increase the default heap size if you plan to export a large number of streams.
Minimum AWS IoT Greengrass Core version: 1.10.0
**Read-only input file directories**
Parameter name: `STREAM_MANAGER_READ_ONLY_DIRS`
A comma-separated list of absolute paths to the directories outside of the root file system that store input files. Stream manager reads and uploads the files to Amazon S3 and mounts the directories as read-only. For more information about exporting to Amazon S3, see [Amazon S3 objects](stream-export-configurations.md#export-to-s3).
Use this parameter only if the following conditions are true:
+ The input file directory for a stream that exports to Amazon S3 is in one of the following locations:
+ A partition other than the root file system.
+ Under `/tmp` on the root file system.
+ The [default containerization](lambda-group-config.md#lambda-containerization-groupsettings) of the Greengrass group is **Greengrass container**.
Example value: `/mnt/directory-1,/mnt/directory-2,/tmp`
Minimum AWS IoT Greengrass Core version: 1.11.0
**Minimum size for multipart upload**
Parameter name: `STREAM_MANAGER_EXPORTER_S3_DESTINATION_MULTIPART_UPLOAD_MIN_PART_SIZE_BYTES`
The minimum size (in bytes) of a part in a multipart upload to Amazon S3. Stream manager uses this setting and the size of the input file to determine how to batch data in a multipart PUT request. The default and minimum value is `5242880` bytes (5 MB).
Stream manager uses the stream's `sizeThresholdForMultipartUploadBytes` property to determine whether to export to Amazon S3 as a single or multipart upload. User-defined Lambda functions set this threshold when they create a stream that exports to Amazon S3. The default threshold is 5 MB.
Minimum AWS IoT Greengrass Core version: 1.11.0
## Configure stream manager settings (console)
You can use the AWS IoT console for the following management tasks:
+ [Check if stream manager is enabled](#check-stream-manager-console)
+ [Enable or disable stream manager during group creation](#enable-stream-manager-console-new-group)
+ [Enable or disable stream manager for an existing group](#enable-stream-manager-console-existing-group)
+ [Change stream manager settings](#change-stream-manager-console)
Changes take effect after the Greengrass group is deployed. For a tutorial that shows how to deploy a Greengrass group that contains a Lambda function that interacts with stream manager, see [Export data streams to the AWS Cloud (console)](stream-manager-console.md).
**Note**
When you use the console to enable stream manager and deploy the group, the memory size for stream manager is set to 4194304 KB (4 GB) by default. We recommend that you set the memory size to at least 128000 KB.
### To check if stream manager is enabled (console)
1. In the AWS IoT console navigation pane, under **Manage**, expand **Greengrass devices**, and then choose **Groups (V1)**.
1. Choose the target group.
1. Choose the **Lambda functions tab**.
1. Under **System Lambda functions**, select **Stream manager**, and choose **Edit**.
1. Check the enabled or disabled status. Any custom stream manager settings that are configured are also displayed.
### To enable or disable stream manager during group creation (console)
1. In the AWS IoT console navigation pane, under **Manage**, expand **Greengrass devices**, and then choose **Groups (V1)**.
1. Choose **Create Group**. Your choice on the next page determines how you configure stream manager for the group.
1. Proceed through the **Name your Group** and choose a **Greengrass core** pages.
1. Choose **Create group**.
1. On the group configuration page, choose the **Lambda functions** tab, select **Stream manager**, and choose **Edit**.
+ To enable stream manager with default settings, choose **Enable with default settings**.
+ To enable stream manager with custom settings, choose **Customize settings**.
1. On the **Configure Stream manager** page, choose **Enable with custom settings**.
1. Under **Custom settings**, enter values for stream manager parameters. For more information, see [Stream manager parameters](#stream-manager-parameters). Leave fields empty to allow AWS IoT Greengrass to use their default values.
+ To disable stream manager, choose **Disable**.
1. On the **Configure stream manager** page, choose **Disable**.
1. Choose **Save**.
1. Continue through the remaining pages to create your group.
1. On the **Client devices** page, download your security resources, review the information, and then choose **Finish**.
**Note**
When stream manager is enabled, you must [install the Java 8 runtime](stream-manager.md#stream-manager-requirements) on the core device before you deploy the group.
### To enable or disable stream manager for an existing group (console)
1. In the AWS IoT console navigation pane, under **Manage**, expand **Greengrass devices**, and then choose **Groups (V1)**.
1. Choose the target group.
1. Choose the **Lambda functions tab**.
1. Under **System Lambda functions**, select **Stream manager**, and choose **Edit**.
1. Check the enabled or disabled status. Any custom stream manager settings that are configured are also displayed.
### To change stream manager settings (console)
1. In the AWS IoT console navigation pane, under **Manage**, expand **Greengrass devices**, and then choose **Groups (V1)**.
1. Choose the target group.
1. Choose the **Lambda functions tab**.
1. Under **System Lambda functions**, select **Stream manager**, and choose **Edit**.
1. Check the enabled or disabled status. Any custom stream manager settings that are configured are also displayed.
1. Choose **Save**.
## Configure stream manager settings (CLI)
In the AWS CLI, use the system `GGStreamManager` Lambda function to configure stream manager. System Lambda functions are components of the AWS IoT Greengrass Core software. For stream manager and some other system Lambda functions, you can configure Greengrass functionality by managing the corresponding `Function` and `FunctionDefinitionVersion` objects in the Greengrass group. For more information, see [Overview of the AWS IoT Greengrass group object model](deployments.md#api-overview).
You can use the API for the following management tasks. The examples in this section show how to use the AWS CLI, but you can also call the AWS IoT Greengrass API directly or use an AWS SDK.
+ [Check if stream manager is enabled](#check-stream-manager-cli)
+ [Enable, disable, or configure stream manager](#enable-stream-manager-cli)
Changes take effect after the group is deployed. For a tutorial that shows how to deploy a Greengrass group with a Lambda function that interacts with stream manager, see [Export data streams to the AWS Cloud (CLI)](stream-manager-cli.md).
**Tip**
To see if stream manager is enabled and running from your core device, you can run the following command in a terminal on the device.
```
ps aux | grep -i 'streammanager'
```
### To check if stream manager is enabled (CLI)
Stream manager is enabled if your deployed function definition version includes the system `GGStreamManager` Lambda function. To check, do the following;
1. Get the IDs of the target Greengrass group and group version. This procedure assumes that this is the latest group and group version. The following query returns the most recently created group.
```
aws greengrass list-groups --query "reverse(sort_by(Groups, &CreationTimestamp))[0]"
```
Or, you can query by name. Group names are not required to be unique, so multiple groups might be returned.
```
aws greengrass list-groups --query "Groups[?Name=='MyGroup']"
```
**Note**
You can also find these values in the AWS IoT console. The group ID is displayed on the group's **Settings** page. Group version IDs are displayed on the group's **Deployments** tab.
1. Copy the `Id` and `LatestVersion` values from the target group in the output.
1. Get the latest group version.
+ Replace *group-id* with the `Id` that you copied.
+ Replace *latest-group-version-id* with the `LatestVersion` that you copied.
```
aws greengrass get-group-version \
--group-id group-id \
--group-version-id latest-group-version-id
```
1. From the `FunctionDefinitionVersionArn` in the output, get the IDs of the function definition and function definition version.
+ The function definition ID is the GUID that follows the `functions` segment in the Amazon Resource Name (ARN).
+ The function definition version ID is the GUID that follows the `versions` segment in the ARN.
```
arn:aws:greengrass:us-west-2:123456789012:/greengrass/definition/functions/function-definition-id/versions/function-definition-version-id
```
1. Get the function definition version.
+ Replace *function-definition-id* with the function definition ID.
+ Replace *function-definition-version-id* with the function definition version ID.
```
aws greengrass get-function-definition-version \
--function-definition-id function-definition-id \
--function-definition-version-id function-definition-version-id
```
If the `functions` array in the output includes the `GGStreamManager` function, then stream manager is enabled. Any environment variables defined for the function represent custom settings for stream manager.
### To enable, disable, or configure stream manager (CLI)
In the AWS CLI, use the system `GGStreamManager` Lambda function to configure stream manager. Changes take effect after you deploy the group.
+ To enable stream manager, include `GGStreamManager` in the `functions` array of your function definition version. To configure custom settings, define environment variables for the corresponding [stream manager parameters](#stream-manager-parameters).
+ To disable stream manager, remove `GGStreamManager` from the `functions` array of your function definition version.
**Stream manager with default settings**
The following example configuration enables stream manager with default settings. It sets the arbitrary function ID to `streamManager`.
```
{
"FunctionArn": "arn:aws:lambda:::function:GGStreamManager:1",
"FunctionConfiguration": {
"MemorySize": 4194304,
"Pinned": true,
"Timeout": 3
},
"Id": "streamManager"
}
```
For the `FunctionConfiguration` properties, you might know the following:
+ `MemorySize` is set to 4194304 KB (4 GB) with default settings. You can always change this value. We recommend that you set `MemorySize` to at least 128000 KB.
+ `Pinned` must be set to `true`.
+ `Timeout` is required by the function definition version, but `GGStreamManager` doesn't use it.
**Stream manager with custom settings**
The following example configuration enables stream manager with custom values for the storage directory, server port, and thread pool size parameters.
```
{
"FunctionArn": "arn:aws:lambda:::function:GGStreamManager:1",
"FunctionConfiguration": {
"Environment": {
"Variables": {
"STREAM_MANAGER_STORE_ROOT_DIR": "/data",
"STREAM_MANAGER_SERVER_PORT": "1234",
"STREAM_MANAGER_EXPORTER_THREAD_POOL_SIZE": "4"
}
},
"MemorySize": 4194304,
"Pinned": true,
"Timeout": 3
},
"Id": "streamManager"
}
```
AWS IoT Greengrass uses default values for [stream manager parameters](#stream-manager-parameters) that aren't specified as environment variables.
**Stream manager with custom settings for Amazon S3 exports**
The following example configuration enables stream manager with custom values for the upload directory and minimum multipart upload size parameters.
```
{
"FunctionArn": "arn:aws:lambda:::function:GGStreamManager:1",
"FunctionConfiguration": {
"Environment": {
"Variables": {
"STREAM_MANAGER_READ_ONLY_DIRS": "/mnt/directory-1,/mnt/directory-2,/tmp",
"STREAM_MANAGER_EXPORTER_S3_DESTINATION_MULTIPART_UPLOAD_MIN_PART_SIZE_BYTES": "10485760"
}
},
"MemorySize": 4194304,
"Pinned": true,
"Timeout": 3
},
"Id": "streamManager"
}
```
**To enable, disable, or configure stream manager (CLI)**
1. Get the IDs of the target Greengrass group and group version. This procedure assumes that this is the latest group and group version. The following query returns the most recently created group.
```
aws greengrass list-groups --query "reverse(sort_by(Groups, &CreationTimestamp))[0]"
```
Or, you can query by name. Group names are not required to be unique, so multiple groups might be returned.
```
aws greengrass list-groups --query "Groups[?Name=='MyGroup']"
```
**Note**
You can also find these values in the AWS IoT console. The group ID is displayed on the group's **Settings** page. Group version IDs are displayed on the group's **Deployments** tab.
1. Copy the `Id` and `LatestVersion` values from the target group in the output.
1. Get the latest group version.
+ Replace *group-id* with the `Id` that you copied.
+ Replace *latest-group-version-id* with the `LatestVersion` that you copied.
```
aws greengrass get-group-version \
--group-id group-id \
--group-version-id latest-group-version-id
```
1. Copy the `CoreDefinitionVersionArn` and all other version ARNs from the output, except `FunctionDefinitionVersionArn`. You use these values later when you create a group version.
1. From the `FunctionDefinitionVersionArn` in the output, copy the ID of the function definition. The ID is the GUID that follows the `functions` segment in the ARN, as shown in the following example.
```
arn:aws:greengrass:us-west-2:123456789012:/greengrass/definition/functions/bcfc6b49-beb0-4396-b703-6dEXAMPLEcu5/versions/0f7337b4-922b-45c5-856f-1aEXAMPLEsf6
```
**Note**
Or, you can create a function definition by running the [https://docs.aws.amazon.com/cli/latest/reference/greengrass/create-function-definition.html](https://docs.aws.amazon.com/cli/latest/reference/greengrass/create-function-definition.html) command, and then copying the ID from the output.
1. Add a function definition version to the function definition.
+ Replace *function-definition-id* with the `Id` that you copied for the function definition.
+ In the `functions` array, include all other functions that you want to make available on the Greengrass core. You can use the `get-function-definition-version` command to get the list of existing functions.
**Enable stream manager with default settings**
The following example enables stream manager, by including the `GGStreamManager` function in the `functions` array. This example uses default values for [stream manager parameters](#stream-manager-parameters).
```
aws greengrass create-function-definition-version \
--function-definition-id function-definition-id \
--functions '[
{
"FunctionArn": "arn:aws:lambda:::function:GGStreamManager:1",
"FunctionConfiguration": {
"MemorySize": 4194304,
"Pinned": true,
"Timeout": 3
},
"Id": "streamManager"
},
{
"FunctionArn": "arn:aws:lambda:us-west-2:123456789012:function:MyLambdaFunction:MyAlias",
"FunctionConfiguration": {
"Executable": "myLambdaFunction.function_handler",
"MemorySize": 16000,
"Pinned": true,
"Timeout": 5
},
"Id": "myLambdaFunction"
},
... more user-defined functions
]
}'
```
The `myLambdaFunction` function in the examples represents one of your user-defined Lambda functions.
**Enable stream manager with custom settings**
The following example enables stream manager by including the `GGStreamManager` function in the `functions` array. All stream manager settings are optional, unless you want to change the default values. This example shows how to use environment variables to set custom values.
```
aws greengrass create-function-definition-version \
--function-definition-id function-definition-id \
--functions '[
{
"FunctionArn": "arn:aws:lambda:::function:GGStreamManager:1",
"FunctionConfiguration": {
"Environment": {
"Variables": {
"STREAM_MANAGER_STORE_ROOT_DIR": "/data",
"STREAM_MANAGER_SERVER_PORT": "1234",
"STREAM_MANAGER_EXPORTER_THREAD_POOL_SIZE": "4"
}
},
"MemorySize": 4194304,
"Pinned": true,
"Timeout": 3
},
"Id": "streamManager"
},
{
"FunctionArn": "arn:aws:lambda:us-west-2:123456789012:function:MyLambdaFunction:MyAlias",
"FunctionConfiguration": {
"Executable": "myLambdaFunction.function_handler",
"MemorySize": 16000,
"Pinned": true,
"Timeout": 5
},
"Id": "myLambdaFunction"
},
... more user-defined functions
]
}'
```
For the `FunctionConfiguration` properties, you might know the following:
+ `MemorySize` is set to 4194304 KB (4 GB) with default settings. You can always change this value. We recommend that you set `MemorySize` to at least 128000 KB.
+ `Pinned` must be set to `true`.
+ `Timeout` is required by the function definition version, but `GGStreamManager` doesn't use it.
**Disable stream manager**
The following example omits the `GGStreamManager` function, which disables stream manager.
```
aws greengrass create-function-definition-version \
--function-definition-id function-definition-id \
--functions '[
{
"FunctionArn": "arn:aws:lambda:us-west-2:123456789012:function:MyLambdaFunction:MyAlias",
"FunctionConfiguration": {
"Executable": "myLambdaFunction.function_handler",
"MemorySize": 16000,
"Pinned": true,
"Timeout": 5
},
"Id": "myLambdaFunction"
},
... more user-defined functions
]
}'
```
If you don't want to deploy any Lambda functions, you can omit the function definition version entirely.
1. Copy the `Arn` of the function definition version from the output.
1. Create a group version that contains the system Lambda function.
+ Replace *group-id* with the `Id` for the group.
+ Replace *core-definition-version-arn* with the `CoreDefinitionVersionArn` that you copied from the latest group version.
+ Replace *function-definition-version-arn* with the `Arn` that you copied for the new function definition version.
+ Replace the ARNs for other group components (for example, `SubscriptionDefinitionVersionArn` or `DeviceDefinitionVersionArn`) that you copied from the latest group version.
+ Remove any unused parameters. For example, remove the `--resource-definition-version-arn` if your group version doesn't contain any resources.
```
aws greengrass create-group-version \
--group-id group-id \
--core-definition-version-arn core-definition-version-arn \
--function-definition-version-arn function-definition-version-arn \
--device-definition-version-arn device-definition-version-arn \
--logger-definition-version-arn logger-definition-version-arn \
--resource-definition-version-arn resource-definition-version-arn \
--subscription-definition-version-arn subscription-definition-version-arn
```
1. Copy the `Version` from the output. This is the ID of the new group version.
1. Deploy the group with the new group version.
+ Replace *group-id* with the `Id` that you copied for the group.
+ Replace *group-version-id* with the `Version` that you copied for the new group version.
```
aws greengrass create-deployment \
--group-id group-id \
--group-version-id group-version-id \
--deployment-type NewDeployment
```
Follow this procedure if you want to edit stream manager settings again later. Make sure to create a function definition version that includes the `GGStreamManager` function with the updated configuration. The group version must reference all component version ARNs that you want to deploy to the core. Changes take effect after the group is deployed.
## See also
+ [Manage data streams on the AWS IoT Greengrass core](stream-manager.md)
+ [Use StreamManagerClient to work with streams](work-with-streams.md)
+ [Export configurations for supported AWS Cloud destinations](stream-export-configurations.md)
+ [Export data streams to the AWS Cloud (console)](stream-manager-console.md)
+ [Export data streams to the AWS Cloud (CLI)](stream-manager-cli.md)