Can I ask a really basic question?
I’ve read lots of references to RBNHole (normally about it’s inner workings and code) and I can see spots on SOTAWatch tagged as 'Posted by RBNHOLE but, what is it?
I’ve assumed it’s a skimmer add-on that looks for ‘CQ SOTA’ calls and creates a spot (as they all seem to be CW) or that it looks at DX boards and spots SOTA references but I’ve really no idea.
What is it and do I need to do anything to benefit from its existence?
Michael (G0POT)
RBNHole is software that compares spots logged on the Reverse Beacon Network (RBN) with alerts posted on sotawatch. Provided there is a match that meets certain criteria, RBNHole posts a spot on Sotawatch to indicate that callsign X has actually been heard calling CQ on frequency X.
There are ways of labelling your alerts to change some of the parameters, from time tolerances to forbidding RBNHole from posting any spots for you.
If you posted an alert for a cw activation and your CQ is “heard” by a RBN monitor (which all run a skimmer system using licenced software) then your CQ will be automatically spotted, so even if you have no internet access and nobody has answered your CQ yet, you could be spotted on SOTAWATCH automatically by this system.
RBNHole was written by Andrew Ryan VK3ARR and is based on the concepts of the RBNgate system originally written by Eric June KU6J (SK).
Hope I’ve got all the details correct. Apologies if not. Andrew is in South Korea and will probably respond when he has time.
Andrew VK1DA VK2UH
That’s it in a nutshell. RBNHole | VK3ARR's SOTA Blog should have a users guide. Third response from Google here for ‘rbnhole’ in Korea, the first two being to reflector topics that discuss the same stuff. Should probably try SEO on that 
I have a company in Bangalore who email me every week about their SEO services. Would you like me to forward your details? 
I think we all get those.
Martin,
Sorry, I re-read your question just now and I realised that my answer drifted off a bit.
Yes, it is cw only. Due to RBN being CW and digi modes only.
You don’t have to do anything other than call cq. If a RBN skimmer station copies you and uploads a spot on the RBN network (you can look for your own spots there) then in due course, within a minute usually, RBNHole will post a spot identifying you and your frequency.
The spot identifies the skimmer station that logged your CQ on RBN.
73 Andrew VK1DA VK2UH
You do have to post an alert!
But we all post alerts, right? 
Indeed, and that was mentioned several times in my earlier response. The more recent response was to answer two specific questions originally asked. For completeness i should have restated that requirement.
For more details, use the search facility on this reflector.
That’s great Andrew and useful to understand the benefit of posting an alert before activating, especially on summits with no coverage.
Thanks,
Michael (G0POT)