Request logging - log backend issues

Hello everyone,

been a happy user of a remote request logging profile for some time now, but recently we had an influx of issues where the backend would be failing in some way or another and the only data of this would be on the clients' side with F5 responding with 'TCP RST' packet, therefore a requirement was raised to log any errors.

Looking at documentation it seemed "Error Template" was exactly for this, so I configured a simple debug profile:

Then tried multiple usecases:

1. backend responds with 200: standard "REQUEST" and "RESPONSE" gets logged
2. backend responds with non-2xx response code: standard "REQUEST" and "RESPONSE" gets logged.
3. backend is down: F5 responds with TCP RST and NOTHING is logged
4. backend is shutdown just as F5 processes the request: REQUEST gets logged, but RESPONSE doesn't and F5 responds with TCP reset

Can someone please share what am I doing wrong or help me understand when is the "Error Template" used? I am clearly misunderstanding it.

Thanks a lot,

Michal.