So, I have tried to start the server 2 times already, 60 minutes in queue each, just to see the Server "Starting" and then suddenly stopped, didn't even go online.
It's Mianite Reborn for 6 people and from what I see in the logs it says:
[17:02:22] [Thread-24/ERROR] [Galacticraft/GalacticraftCore]: Galacticraft update check failed! Trying again in 15 seconds
[17:02:25] [Thermos version retriever/WARN] [Thermos: TVersionRetriever/]: Error occured during retriving version
[17:02:37] [Thread-24/ERROR] [Galacticraft/GalacticraftCore]: Galacticraft update check failed! Trying again in 15 seconds
[17:02:53] [Thread-24/ERROR] [Galacticraft/GalacticraftCore]: Galacticraft update check failed! Trying again in 15 seconds
I'm currently in queue(70 mins) for the third time to see if I can get lucky and it starts, yesterday it worked perfectly tho.
It seems to be the galacticraft update. If I can give more info to you guys I can gladly do it. I just don't know much about servers. Thanks 
EDIT: Third time and got it for some random reason. Didn't change a damn thing. Thanks anyways!