Zombies treat open iron doors as walls and will not pursue the player through them. If the door is destroyed then the zombies will continue to follow the player. Baby zombies do not appear to have this limitation. This behavior is always consistent and reproducible on SMP, but seems to exist in SP as well.
What I expect to happen is the zombies to follow the player anywhere the player goes, including through iron doors that are open long enough for the zombie to get through. I've noticed this for the last several MC/PC releases (back at 1.8, if not earlier), and am not exactly sure when this started.
Comments 5
Sorry, misread. However this is a duplicate of MC-102896.
I am not sure about that either. I can't speak for passive mobs, but I've had skeletons and creepers walk through (open) wood and iron doors to get me. It's only adult zombies that I've seen absolutely refuse to pursue me through an open iron door (single or double). Not only that, but once I am through the open door, they forget I exist and walk off to other targets (villagers).
Zombies are included in MC-102896. See the attachment.
This bug is not a duplicate of MC-50556. That bug appears to address iron trap doors, and their positioning inconsistencies. I made no mention of trap doors at all, and instead refer to regular iron doors placed normally.