So the event happened with a zombie dissapiaring right before me, even though the server was working fine beforehand. Then I entered a building and saw a zombie. I shot him once with Makarov, it was a clear headshot, yet he didn't die and even did not react. Then I started to record the video attached below. In the video I shoot the same zombie in the head one more time and he's still alive and dies only when I hit him in the shoulder. After that a zombie aggroes which looks like the one that dissapiared at the beginning, and he also appears to be somewhat immune to headshots. All of thisis happening while I'm staying close to a building entrance, just between the doors, and I'm also shooting through door openings.

Video: https://youtu.be/J_CzMw3BRrk
Community Server "DayZ Village"