SignalResource - Amazon CloudFormation
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Sends a signal to the specified resource with a success or failure status. You can use the SignalResource operation in conjunction with a creation policy or update policy. Amazon CloudFormation doesn't proceed with a stack creation or update until resources receive the required number of signals or the timeout period is exceeded. The SignalResource operation is useful in cases where you want to send signals from anywhere other than an Amazon EC2 instance.

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.


The logical ID of the resource that you want to signal. The logical ID is the name of the resource that given in the template.

Type: String

Required: Yes


The stack name or unique stack ID that includes the resource that you want to signal.

Type: String

Length Constraints: Minimum length of 1.

Pattern: ([a-zA-Z][-a-zA-Z0-9]*)|(arn:\b(aws|aws-us-gov|aws-cn)\b:[-a-zA-Z0-9:/._+]*)

Required: Yes


The status of the signal, which is either success or failure. A failure signal causes Amazon CloudFormation to immediately fail the stack creation or update.

Type: String


Required: Yes


A unique ID of the signal. When you signal Amazon EC2 instances or Auto Scaling groups, specify the instance ID that you are signaling as the unique ID. If you send multiple signals to a single resource (such as signaling a wait condition), each signal requires a different unique ID.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 64.

Required: Yes


For information about the errors that are common to all actions, see Common Errors.



This example illustrates one usage of SignalResource.

Sample Request ?Action=SignalResource &LogicalResourceId=MyWaitCondition &StackName=AWaitingTestStack &Status=SUCCESS &UniqueId=test-signal &Version=2010-05-15 &SignatureVersion=2 &Timestamp=2010-07-27T22%3A26%3A28.000Z &AWSAccessKeyId=[AWS Access KeyID] &Signature=[Signature]

Sample Response

<SignalResourceResponse xmlns=""> <ResponseMetadata> <RequestId>e7d8c346-744b-11e5-b40b-example</RequestId> </ResponseMetadata> </SignalResourceResponse>

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: