This is a response from the CDF API that usually means the RAW service itself is overloaded. It is something that generally should not happen, and is usually only an intermittent error when it does.
The DB extractor will retry failing requests towards CDF a number of times, that’s why this is a warning log and not an error log (at least not yet), since the extractor will retry the request again several times. If it eventually gave up you will see a log line in the `ERROR` channel telling you so. If that happens, the extractor could be picking up that data again next time it runs, depending on how you have configured state stores and incremental fields in your configuration file.