Luckily never saw something like that in any of my worlds, does it happens only in multiplayers games or also in solo one ?

I've never seen something like that either - must be multiplayer o.o

Yeah, looks to be a multiplayer bug.

Damned annoying though! The missing chunks are always in the most awkward of places.

I took two screenies of even worse a couple of days earlier:

Disconnecting and logging back in fixes the missing chunks, but it is still really annoying.

So it turns out a chunk reset thing has happened and it's deleted part of the outside wall. Now the monster trap is even less functional. D:

I'm currently on the server, but I'm stuck in my mine till daybreak, then I'll do what I can to repair the damage.

Edit: Holy crap, this could take a while...

Edit2: Okay, the wall is up, I'm working on repairing "The Vault" right now, but I don't remember exactly how it looked, anyone able to help? At least with information, if not with your pick?

Edit3: Well, it's not perfect; the moat is mostly fixed, the buildings have walls, but the interior of the vault still has large holes in it.

Upgrading the grinder to use a lava-based edge (as described here) would solve the problem of mobs not being pulled under--with this design water pushes them onto the ladder which they then climb to no avail while burning to death. This design can even grind spiders.

Anyone willing to fetch about 80 buckets of lava and build hundreds of ladders? ;)

It didn't fix the tower, nor restarting the server or anything.

I had to rebuild it.

Kalas is talking about chunks that are invisible client-side (see the attached screenshots above), not ones that have disappeared server-side and been replaced with newly-generated terrain. Client-side issues are easily fixed by logging out while no magic other than restoring a backup can recover a deleted chunk.

The mine I'm digging right now leads to some nice lava pools that we can harvest if you like.

Hi folks,

Have been meaning to join for a while, but have recently joined the server. I'm getting set up now, but will be more than willing to help out once I get myself established.

I think the best way to keep that from happening is to put up a sign; we're OK folks and if we know that you're actively working on something we'll keep away until you say that you need some help.

I hide stuff I don't want anyone else touching. :P