@vikrant_kumar24 Based on what you describe you are either exceeding the capabilities of the outbound network connection from nifi, or the receiving end API. I suspect the latter but its hard to tell without seeing the number of nodes and processor scheduling settings. You can try to slow down the execution of invokeHttp to confirm. If it is set to 0 sec it can create a lot of connections to the endpoint. Try 5,10,15 seconds and re-evaluate. Also If you have more than 1 one nifi node, it can create a great deal of concurrent connections.
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