Just a couple of environment variables and arguments, simply do the following:

export VLLM_LOGGING_LEVEL=DEBUG
export VLLM_DEBUG_LOG_API_SERVER_RESPONSE=TRUE

vllm serve \
--enable-log-requests \
--enable-log-outputs 2>&1 | tee vllm_server.log

That’s it, Enjoy!

Source:

• Gemini!