How do I use _xpack/ml/datafeeds API?

Elastic Stack Elasticsearch
1

I have a few ML jobs. I would like to start them pragmatically. The docs suggest the use of the below API.

I would like to start at the beginning of data, and let it continue forever (no real end time)
What should be my start / stop / timeout parameters in this case?

POST _xpack/ml/datafeeds/datafeed-dns-rate-and-size/_start
{
  "start": "",
  "stop": "",
  "timeout": ""
}
2

Just specify a start time that is earlier than your earliest timestamp of the dataset and do not specify a stop time. For example:

POST /_xpack/ml/datafeeds/datafeed-asamplejob/_start?start=2018-01-01T00:00:00Z