Retry a Failed HTTP Request

To retry an HTTP request when the server returns an HTTP error:

1. In a defaults or backend section of your load balancer configuration, set the retries directive to the number of times to retry a failed HTTP request.

   Attempt to connect to the server 5 times before giving up and returning the HTTP error.

   backend webservers
      mode http
      retries 5

2. Add the retry-on directive to define specific types of HTTP errors that should trigger a retry. Options include:

   • 404

   • 408

   • 425

   • 500

   • 501

   • 502

   • 503

   • 504

   • all-retryable-errors

   Retry when the request fails due to failure 503 or 504.

   backend
      retry-on 503 504

3. Optional: Add to the retry-on directive specific types of TCP connection problems that should trigger a retry, in addition to HTTP conditions. Options include:

   • conn-failure

   • empty-response

   • response-timeout

   • 0rtt-rejected

   • all-retryable-errors

   Retry the connection if the connection could not be established or was closed while sending the request.

   backend
      retry-on conn-failure empty-response 500

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