Hello, I was playing jazz long time ago and I remember that I was playing on some kind of parkour servers. You had obstacle course to pass and I remember it was challenging. Are these servers still ON or they are dead? Or maybe anyone got map pack for it?
Thank you for your help.

Multiplayer-compatible obstacle course levels generally go by the name of "tests". There is currently a dedicated 24/7 test server named Puke Nuk3m Tests, and specific test levels can be played in Puke Nuk3m Arena servers if you know what you're looking for. Tests also have a download category on J2O, but this is a recent addition and many older downloads are still listed in other categories.

Note that over the years, test levels exhibited a tendency for steeply rising difficulty. Many modern tests are incomparably harder to finish than what you might remember, and may require a lot of trial and error, as well as tricks and glitches that are unknown to beginners. Good luck.