Lambda includes a State field in the function configuration for all functions to indicate when your function is ready to invoke. State provides information about the current status of the function, including whether you can successfully invoke the function. Function states do not change the behavior of function invocations or how your function runs the code.
Note
Function state definitions differ slightly for SnapStart functions. For more information, see Lambda SnapStart and function states.
Function states include:
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Pending– After Lambda creates the function, it sets the state to pending. While in pending state, Lambda attempts to create or configure resources for the function, such as VPC or EFS resources. Lambda does not invoke a function during pending state. Any invocations or other API actions that operate on the function will fail. -
Active– Your function transitions to active state after Lambda completes resource configuration and provisioning. Functions can only be successfully invoked while active. -
Failed– Indicates that resource configuration or provisioning encountered an error. -
Inactive– A function becomes inactive when it has been idle long enough for Lambda to reclaim the external resources that were configured for it. When you try to invoke a function that is inactive, the invocation fails and Lambda sets the function to pending state until the function resources are recreated. If Lambda fails to recreate the resources, the function returns to the inactive state. You might need to resolve any errors and redeploy your function to restore it to the active state.
If you are using SDK-based automation workflows or calling Lambda’s service APIs directly, ensure that you check a function's state before invocation to verify that it is active.
You can do this with the Lambda API action GetFunction, or by configuring a waiter using the
AWS SDK for Java 2.0
aws lambda get-function --function-name my-function --query 'Configuration.[State, LastUpdateStatus]'
You should see the following output:
[ "Active", "Successful" ]
The following operations fail while function creation is pending:
Function states during updates
Lambda has two operations for updating functions:
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UpdateFunctionCode: Updates the function's deployment package
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UpdateFunctionConfiguration: Updates the function's configuration
Lambda uses the LastUpdateStatus attribute to track the progress of these update operations. While an update is in progress (when "LastUpdateStatus": "InProgress"):
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The function's State remains
Active. -
Invocations continue to use the function's previous code and configuration until the update completes.
-
The following operations fail:
Example GetFunctionConfiguration response
The following example is the result of GetFunctionConfiguration request on a function undergoing an update.
{ "FunctionName": "my-function", "FunctionArn": "arn:aws:lambda:us-east-1:123456789012:function:my-function", "Runtime": "nodejs22.x", "VpcConfig": { "SubnetIds": [ "subnet-071f712345678e7c8", "subnet-07fd123456788a036", "subnet-0804f77612345cacf" ], "SecurityGroupIds": [ "sg-085912345678492fb" ], "VpcId": "vpc-08e1234569e011e83" },"State": "Active", "LastUpdateStatus": "InProgress", ... }
