I have a setup with a specific sourcetype defined (rfc5424_syslog), which works fine over TCP, but when exactly the same data is received over UDP is seems to get automatically broken into fields by Splunk which do not match the source type I'm using. Even the _raw fields contains reformatted data, whereas the _raw field from the TCP source is precisely as sent.
Does anyone know what I need to do to stop Splunk automatically reformatting the data when received over UDP?
Answer provided by Splunk support, in case anyone else needs it, is to add this line to the inputs.conf entry that specified the UDP port:
no_priority_stripping = true