529 The service is overloaded
HTTP response status code 529 The service is overloaded is an unofficial server error that is specific to Qualys. This HTTP status code occurs when the service is overloaded.
When the 529 The service is overloaded status code is received, the server is overloaded and is unwilling to process the HTTP request. This is likely the result of the server receiving too many HTTP requests, however the HTTP client may not have exceeded their limit. Instead, HTTP clients that make too many HTTP requests in a brief period of time, the 429 Too Many Requests status code is sent. The 529 The service is overloaded status code is sent when the total number of HTTP requests, across all HTTP clients, is more than the server can handle at that moment.
This HTTP status code tends to be temporary, depending on the server resources and number of ongoing HTTP requests made, and more often can be remedied by resubmitting the HTTP request at another time, such as during off-peak hours.
The 529 The service is overloaded status code is a Qualys-specific server error that is generated when a server is overloaded and cannot process new HTTP requests.