How to debug "SSL error" on https test(s)?

I'd be trying to do with with
  xymoncmd xymonnet --no-update --debug hostname

Then I can play with the various --ssl options to see if they made any difference.

And now it's green.    **And I've changed nothing**

I am writing this off to "solar flares".

That said, thank you for the info, THAT gave me useful debugging.    I will file that for future use.