Avoid scheduling tasks in vacation in orgmode

Question

I recently started using orgmode and I wonder if there is any way to avoid scheduling (or deadlineing) tasks during my week of vacation. I already found a way to highlight regional holidays (followed by (calendar-mark-holidays).

Now I would like to also highlight my planned vacation or trigger a warning when I schedule a task in the week.

My specific questions would be:

1. Is it at all possible to achieve something like this?
2. If possible, how would I have to store (or schedule) my vacation within the org-document(s)?
3. If possible, how could I ask the orgmode calendar to parse these dates and mark them / trigger a warning?

Let's assume I planned my vacation for one the time period

* Holidays
** Autumn Holiday
   <2019-10-07 Mon> - <2019-10-27 Sun>

Answer 1

I found a solution and will leave that here (in case any beginners like me search for that in the future). Yet, I will be happy to accept any other, probably more elegant, solution.

First create a diary file:

Ctrlx Ctrlf ~/.emacs.d/diary

Then add the entries according to the diary time format, e.g.:

%%(diary-block 10 07 2019 10 27 2019)   Vacation

Add the following lines to your configuration (or init.el):

(setq calendar-mark-diary-entries-flag t)
(setq org-agenda-include-diary t) ;; include the diary entries in agenda buffer

This displays the holidays in the popup calendar buffer and I will use that to avoid scheduling stuff during my vacation.