Repercussions for deleting level.dat?

[Roachy]

Hi, I recently had a problem where my FTB server's world got corrupted and it would only run for a minute or so before hanging. After fooling around with it for a while I managed to fix this problem by deleting the world's level.dat and level.dat_old.

I was under the impression that level.dat held data pertaining to things like the world seed, player inventory, world spawn point, etc. However nothing appears out of the ordinary after deleting this file. My inventory was intact, my bed-spawnpoint hadn't been reset. I even broke my bed and killed myself and ended up spawning in what I think was the original world spawn point (although it's been so long I can't remember exactly). The world seed on the other hand does appear to have changed.

Should I be worried about any repercussions other than new world gen being a little funky? And I don't suppose there's a way to modify the world's seed? If possible I'd prefer to keep my seed so I don't end up getting odd world gen at some point (although I've explored so much it would be a long time before that happened).

Is there an editor I can use to compare my old and new level.dats?

Thanks for any assistance.

 

[Roachy]

Update: Well I found NBTExplorer to compare the files. They're nearly the same, the only differences being some time/weather settings, the world spawn is slightly different, and the world seed is different. Other than that I see no differences, and don't notice any form of corruption in the old one offhand.

Update 2: Even more bizarre. I backed up the new, good level.dat file and modified it with NBTExplorer. All I did was copy the seed from the old busted level.dat into the new one and save it. Then I ran the server and it had the crash issue again. I restored the good level.dat and no more problems again. Either NBTExplorer isn't saving the file correctly, or the... seed? is corrupt? Another strange thing I noticed since I got the server working again is that now all of my Thaumcraft nodes pulsate. I saw them do this in various youtube videos and always wondered why mine didn't. I guess I can't complain.

Update 3: Well I've found a serious repercussion. It would seem that certain biome data has changed or been lost. All of the sudden all of my bees think they are in a hostile environment, even though F3 shows the biome names as they should be, rendering my entire brand new bee facility useless D:

Update 4: It seems the biome/environment issue is tied to the world seed. I've tried generating a brand new world with the original world's seed, and copying that new world's level.dat files to the working server. That does fix the biome issue but also causes the server to crash again. I'm kind of stumped. I need my original seed back, but however I attempt to accomplish that I am met with server crashes...

 

[Moasseman]

Weeeee neeeeeed a crash repoooooooooooooort

 

[Roachy]

My apologies. I should have been more detailed, but I was only intending to discuss the level.dat weirdness in this topic, and not the server crashing, as I have a ticket open for that. However now that it's become pertinent; The server does not technically crash, it hangs, causing my player to time out and the server to become unresponsive. At this point I have to manually kill the server process and there are thus no logs generated past the startup stuff. Here is the entire ForgeModLoader log from one such occurrence: http://pastebin.com/h79p5Wme

Further information: yesterday, the server was running stable with the new level.dat, for much longer than the 1 minute it would run using the old level.dat. Like I said the only problem I ran into was apiaries repoting hostile environments when they shouldn't. Then I decided to break one of the offending apiaries and replace it. Once I did this it no longer reported the hostile environment, but shortly afterward the server crashed again. So I don't know if it's related to the apiaries or not. Once I got it back up I removed my primary apiary setup (including about half of my total apiaries), threw everything in a chest and let the server run overnight, leaving my client connected. This morning it was still running smoothly.

Just now I placed down a single apiary and threw a queen in for one cycle. No problems. Then I moved into its original position (where I broken/replaced it and the server had crashed the night before). It's now run fine through a whole cycle. So everything appears to be working. I have no idea what the problem with hostile environments was before.

I still have a copy of the old server as it was when it first started crashing, in case my support ticket comes through with something to try.

 

[Roachy]

The people from the forestry IRC inform me that the apiaries only poll the biome/seed location when placed. This explains the hostile environment thing and why replacing the apiary fixed that. Not sure what the hang afterwards was about but everything seems stable today now that I'm going around replacing apiaries.