Good evening, While parsing data from some of my measurements (using ripe.atlas.sagan) I stumbled over the “TU_BAD_ADDR” error. The error message is only “true” which makes it difficult to understand its origin. Furthermore, as opposed to other errors, such as “timeout”, no error is indicated by the is_error method of the DnsResult object. Instead I can only find this in the raw_data (in the dns respone object). In my measurements I send the same DNS query (using probe’s IPv6-address) to public resolver and the probes local resolver over UDP and TCP respectively. The TU_BAD_ADDR error occurred solely on measurements to the probes local resolver over TCP. Respective measurements using the same probes over UDP do not report this error. Another observation is that the source address of the response is not set in the majority of the cases (but that is not always the case). An example measurement is #41853554 (the counter-measurement over UDP #41853806). Does anyone know more about this? Best regards, Meikel