Clarification of "request-log" profile

I am hoping someone with experience with "request-log" profile can answer...

 

Q1. What does "log-response-by-default" attribute (aka. Log By Default) do?

 

Q2 My understanding is that if logging configured by this profiles fails and if "proxy-respond-on-logging-error" is set to "yes" then BIG-IP system will either:

 

(a) itself respond to the client with message in "proxy-response", instead of proceeding with establishment of server-side connection; or

 

(b) will proceed with establishment of server-side connection, forward the request to the server (and perhaps, receive response) but will respond with to the client with message in "proxy-response" anyway.

 

Is my understanding correct? If so, which (a) or (b)?

 

Q3. is termination of client-side connection associated with "proxy-close-on-error" dependent on "proxy-respond-on-logging-error" being set to "yes"?

 

R's, Alex