This API is used to send a signal to a stack resource to change the resource orchestration.

POST /v1/{project_id}/stacks/{stack_name}/{stack_id}/resources/{resource_name}/signal

For details about the parameters, see Table 1.

**Table 1** Parameter description
Parameter	Type	Mandatory	Description
project_id	String	Yes	Specifies the project ID.
stack_name	String	Yes	Specifies the stack name.
stack_id	String	Yes	Specifies the stack UUID.
resource_name	String	Yes	Specifies the name of the resource in the stack.

The requested content is determined by the stack resource to which the signal is to be sent. Some resources cannot receive signals.

This API is asynchronous. Status code 200 is returned if the request is successfully received.

This operation does not return the response body.

POST /v1/95d02433133a4c0a87ba6967474a2ad3/stacks/HeatStack/65eb0ae7-36de-4104-aace-6bd040a2f95f/resources/my_instance/signal

None

**Table 2** Normal return code
Return Code	Type	Description
200	OK	Request was successful.

**Table 3** Error return code
Return Code	Type	Description
400	Bad Request	The server failed to process the request.
401	Unauthorized	Authorization failed.
404	Not found	The requested resources are not found.

Sending a Signal to a Stack Resource